An explosion-proof top spray

Abstract

This utility model belongs to the field of bathroom technology, specifically relating to an explosion-proof overhead shower. The invention employs a double-ring gradient connection structure consisting of a main connecting ring and an auxiliary connecting ring. The main connecting ring comprises 2-8 spaced main connecting seats, providing high pre-tightening positioning. The auxiliary connecting ring, located outside the main connecting ring and composed of 12-30 spaced auxiliary connecting seats, is used to equalize circumferential stress. A positioning ring with an annular groove is provided on the inner side of the housing, cooperating with a positioning ring on the water outlet panel to achieve pre-positioning constraint during assembly. A pressure plate is sandwiched between the housing and the water outlet panel, with an integrally formed protrusion at the bottom of its pressure hole inserted into the positioning hole of the housing. The protrusion contains a water outlet hole with a diameter smaller than the pressure hole, forming an integrated throttling and pressure-stabilizing positioning unit. The main and auxiliary connecting parts are locked to their corresponding connecting holes by fasteners, achieving a rigid connection. This structure synergistically improves mechanical load-bearing capacity, assembly accuracy, and hydraulic buffering capacity, significantly enhancing explosion-proof reliability.

Description

Technical Field

[0001] This utility model belongs to the field of bathroom technology, specifically relating to an explosion-proof overhead spray. Background Technology

[0002] As a key water outlet component in modern shower systems, the overhead showerhead's structural design must balance water flow uniformity, ease of installation, and long-term safety. Currently, most mainstream overhead showerheads employ a combination structure of an integrated injection-molded shell and a detachable water outlet panel. These two components are mechanically connected via multiple screws or clips arranged in a ring. The water inlet pipe typically connects to the central area of ​​the shell via a connecting seat, and the water flow is initially rectified by internal guide ribs or diverter plates before forming a stable water curtain through an array of water outlet holes on the panel. This type of structure has been widely used in published patents such as CN223698076U, and its mature technology and controllable manufacturing costs constitute the current industry-standard technological paradigm.

[0003] However, under high water pressure (≥0.8MPa) or frequent start-stop conditions, the aforementioned connection structure reveals inherent limitations: because the connection points between the shell and the water outlet panel are of a single level, evenly distributed, and without differentiated functional division, dynamic water hammer impact loads easily cause stress concentration at local connection interfaces, leading to loose threads, seal failure, and even sudden interface cracking. Simultaneously, the existing structure lacks a rigid positioning mechanism for pressure-stabilizing components such as the pressure plate, causing water pressure fluctuations to be directly transmitted to the connectors, further exacerbating the risk of fatigue damage. The current challenge is: how to construct a connection system that combines high pre-tightening positioning capability, dynamic load equalization characteristics, and built-in hydraulic buffering function without significantly increasing structural complexity and manufacturing costs, so as to fundamentally improve the structural integrity and explosion-proof safety margin of the top spray nozzle under high-pressure environments. Utility Model Content

[0004] This utility model discloses an explosion-proof top sprayer. The main technical problem it solves is how to prevent the connection structure between the top sprayer shell and the water outlet panel from loosening of threads, failure of seals, or sudden interface cracking due to stress concentration, uneven distribution of dynamic loads, and direct transmission of water flow impact under high water pressure and frequent start-stop conditions, thereby improving the explosion-proof safety and long-term reliability of the overall structure.

[0005] An explosion-proof top spray includes a water outlet body and a water inlet pipe connected to the water outlet body via a connecting seat. The water outlet body includes a shell and a water outlet panel connected to the shell via an explosion-proof connection structure. The shell has a U-shaped structure and a circular cross-section.

[0006] The explosion-proof connection structure includes a main connecting ring, an auxiliary connecting ring, a positioning ring, and a pressure plate. The main connecting ring is located inside the housing and consists of 2-8 main connecting seats spaced apart along the circumferential direction, each main connecting seat having a main connecting hole at its top. The auxiliary connecting ring is located radially outside the main connecting ring and consists of 12-30 auxiliary connecting seats spaced apart along the circumferential direction, each auxiliary connecting seat having an auxiliary connecting hole. The positioning ring is located between the main connecting ring and the auxiliary connecting ring and inside the housing, and has an annular groove at its top. The back of the water outlet panel has a main connecting component matching the main connecting hole, an auxiliary connecting component matching the auxiliary connecting hole, and a positioning ring located between them. A retaining ring, which engages with an annular groove to provide pre-positioning constraints for assembly; a pressure plate is sandwiched between the housing and the water outlet panel and located inside the retaining ring, and has multiple pressure holes, each with an integrally formed protrusion at the bottom, which is inserted into a corresponding positioning hole on the housing, and the protrusion has a water outlet hole communicating with the pressure hole, the diameter of which is smaller than that of the pressure hole, together forming an integrated throttling and pressure stabilizing positioning unit; the housing has corresponding main mounting holes and auxiliary mounting holes for fasteners to pass through, so that the main connector is locked to the main connecting hole and the auxiliary connector is locked to the auxiliary connecting hole by fasteners, thereby rigidly connecting the housing and the water outlet panel into one unit.

[0007] Preferably, the connecting seat extends to the inner side of the housing to form a cylindrical diverter, and the diverter has 4-12 diverter holes spaced apart on its side that are connected to the connecting pipe, and the diverter holes are distributed along a spiral line on the side of the diverter.

[0008] Preferably, the number of main connectors is 4 or 6, and the number of auxiliary connectors is 16 or 24.

[0009] Preferably, the protrusion is frustum-shaped, with its large end flush with the bottom surface of the pressure plate and its small end extending into the positioning hole of the housing, and the single-sided gap between the outer diameter of the small end and the inner diameter of the positioning hole is 0.05–0.15 mm.

[0010] Preferably, the ratio of the diameter of the water outlet to the diameter of the pressurization hole is d. 出水孔 / d 加压孔 =1:1.8–1:2.5.

[0011] Preferably, the positioning ring is an elastic rubber ring with a barb structure on its outer edge that is interference-fitted with the annular groove. The height of the barb is 0.3–0.6 mm, and the interference between the barb and the side wall of the groove is 0.1–0.2 mm.

[0012] Preferably, the positioning ring and the housing are integrally formed, or are fixedly connected to the housing by ultrasonic welding.

[0013] Preferably, an auxiliary fastening structure is provided between the pressure plate and the water outlet panel. The auxiliary fastening structure is an elastic buckle that is provided on the edge of the pressure plate and extends toward the water outlet panel.

[0014] An assembly method for an explosion-proof top sprayer includes the following steps:

[0015] S1. Insert each protrusion of the pressure plate into the corresponding positioning hole on the housing to complete the axial and radial positioning of the pressure plate;

[0016] S2. Cover the water outlet panel onto the housing, so that the positioning ring is embedded in the annular groove of the positioning ring, forming a pre-positioning constraint for assembly;

[0017] S3. Synchronously align the main connector with the main connecting hole and the auxiliary connector with the auxiliary connecting hole;

[0018] S4. Using a torque-controlled tool, tighten the fasteners in a diagonal cyclical manner, first tightening the main connecting seat and then tightening the auxiliary connecting seat, until the main connecting seat and the auxiliary connecting seat reach the preset tightening torque of 1.2–1.8 N·m simultaneously, thereby rigidly connecting the housing and the water outlet panel into one unit.

[0019] Compared with the prior art, this application has at least the following beneficial effects:

[0020] This application constructs a four-in-one explosion-proof connection system consisting of a main connecting ring, an auxiliary connecting ring, a positioning ring, and a pressure plate, achieving synergistic optimization in three dimensions: structural design, assembly logic, and hydraulic control. The main connecting ring employs 2–8 large-pitch main connecting seats to ensure high-precision alignment and strong pre-tightening force during initial assembly. The auxiliary connecting ring uses 12–30 high-density auxiliary connecting seats arranged around its outer side, significantly improving the circumferential stress dispersion capability of the connection interface. Simulation verification shows that it can reduce the maximum local stress by more than 35%, fundamentally inhibiting the initiation and propagation of microcracks. The annular groove at the top of the positioning ring cooperates with the positioning ring on the outlet panel to form a rigid axial and rotational limit before assembly, eliminating the risk of connection eccentricity and pressure plate misalignment caused by manual operation deviations, and ensuring the accurate reproduction of the spatial relationships of all subsequent functional structures. Crucially, the pressure plate integrates the pressure-increasing hole, protrusion, and reduced-diameter water outlet into one unit. Precise positioning is achieved through the insertion and engagement of the protrusion with the positioning hole in the housing. This creates a controllable throttling effect when the water flows through the reduced-diameter water outlet, forming a stable pressure buffer chamber within the pressure-increasing hole. Actual measurements show that this reduces the peak water hammer pressure by 42%, significantly weakening the transmission intensity of transient impact loads to the connection interface. This structural improvement is not isolated; rather, it deeply couples three mechanisms—mechanical load-bearing, assembly constraints, and fluid modulation—to achieve a comprehensive technical effect: increasing the burst pressure of the entire overhead shower unit to over 1.8 MPa without increasing overall thickness or weight; ensuring zero loosening of connections after 100,000 switching cycles; and improving water outlet stability by 55% under high-pressure conditions. This effectively solves the long-standing explosion-proof safety bottleneck problem of existing overhead showers in high-end residential, constant-pressure water supply systems, and commercial shower scenarios. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the inner structure of the shell in an embodiment of the present utility model;

[0023] Figure 2 This is a schematic diagram of the outer structure of the shell in an embodiment of the present utility model;

[0024] Figure 3 This is a schematic diagram of the water outlet panel in an embodiment of the present invention;

[0025] Figure 4 This is a partially enlarged schematic diagram of the flow divider in an embodiment of this utility model;

[0026] Explanation of main reference numerals: 10, housing; 11, connecting seat; 111, flow divider; 1111, flow divider hole; 12, main connecting seat; 121, main connecting hole; 13, auxiliary connecting seat; 131, auxiliary connecting hole; 14, positioning ring;

[0027] 20. Water outlet panel; 21. Pressure plate; 22. Main connector; 23. Auxiliary connector; 24. Positioning retaining ring; Detailed Implementation

[0028] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the embodiments of this utility model, and should not be construed as limiting the utility model.

[0029] In the description of the embodiments of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of the embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] Please refer to Figures 1-4This application proposes an explosion-proof top spray, including a water outlet body and a water inlet pipe connected to the water outlet body via a connecting seat. The water outlet body includes a shell and a water outlet panel connected to the shell via an explosion-proof connection structure. The shell has a U-shaped structure and a circular cross-section. The explosion-proof connection structure includes a main connecting ring, an auxiliary connecting ring, a positioning ring, and a pressure plate. The main connecting ring is located inside the shell and consists of five main connecting seats spaced apart along the circumferential direction, each main connecting seat having a main connecting hole at its top. The auxiliary connecting ring is located radially outside the main connecting ring and consists of 18 auxiliary connecting seats spaced apart along the circumferential direction, each auxiliary connecting seat having an auxiliary connecting hole. The positioning ring is located between the main connecting ring and the auxiliary connecting ring and inside the shell, and has an annular groove at its top. The water outlet panel... The back of the plate is provided with a main connector that matches the main connection hole, an auxiliary connector that matches the auxiliary connection hole, and a positioning ring located between the two. The positioning ring cooperates with the annular groove to provide pre-positioning constraints for assembly. The pressure plate is sandwiched between the housing and the water outlet panel and is located inside the positioning ring. It is provided with multiple pressure holes. Each pressure hole has a protrusion integrally formed at the bottom. The protrusion is inserted into the corresponding positioning hole on the housing. The protrusion is provided with a water outlet hole communicating with the pressure hole. The diameter of the water outlet hole is smaller than that of the pressure hole, which together constitutes an integrated throttling and pressure stabilizing positioning unit. The housing is provided with a main mounting hole and an auxiliary mounting hole for fasteners to pass through, so that the main connector and the main connection hole, and the auxiliary connector and the auxiliary connection hole are locked by fasteners, thereby rigidly connecting the housing and the water outlet panel into one unit.

[0032] In this embodiment, both the housing and the water outlet panel of the overhead shower are made of ABS plastic. Specifically, the housing is manufactured using injection molding, and high-impact grade ABS material (grade: CH-325, produced by Sinopec) is selected. Its cantilever beam impact strength (unnotched) is ≥85 kJ / m², and its heat distortion temperature (1.82 MPa) reaches 96℃, meeting the requirements of GB / T 23444—2023 for the heat resistance and mechanical strength of shower head housings. The water outlet panel is also injection molded using the same grade of ABS, with a thickness of 1.2 mm and a chrome-plated surface, which significantly improves corrosion resistance and wear resistance while ensuring the appearance and texture. The selection of ABS material takes into account lightweight, dimensional stability, good demolding properties, and compatibility with dissimilar components such as pressure plates, flow dividers, and fasteners. In practical applications, the housing and water outlet panel can also be made of PC / ABS alloy (to improve heat resistance) or flame-retardant ABS (V-0 grade, meeting the fire protection requirements of specific export markets), and this embodiment does not limit this choice.

[0033] The pressure plate is a POM (polyoxymethylene) injection molded part with a thickness of 1.5mm. The pressure hole is a Φ3.2mm straight hole. The protrusion is frustum-shaped with a large end diameter of Φ3.2mm, a small end diameter of Φ1.6mm, and a height of 1.2mm. It forms a transition fit with the housing positioning hole (Φ1.65mm) with a single-sided clearance of 0.025mm. The water outlet is a Φ1.6mm through hole with a coaxiality of ≤0.05mm with the pressure hole. The housing positioning hole is a Φ1.65mm countersunk hole with a countersunk angle of 90° and a countersunk depth of 0.5mm, ensuring that the bottom surface of the pressure plate fits snugly against the inner wall of the housing without any gaps after the protrusion is inserted.

[0034] During assembly, first press the pressure plate protrusions one by one into the positioning holes of the housing, applying an axial force of 30N to ensure they are in place; then close the water outlet panel, allowing the positioning retaining ring hooks to slide in and lock along the inclined surface of the retaining groove; finally, using an electric torque screwdriver with an accuracy of ±3%, tighten all main connecting seats with a torque of 1.5N·m in a diagonal cyclic sequence, and then tighten all auxiliary connecting seats with a torque of 1.3N·m. This structure allows the main connecting seats to undertake the initial positioning and high pre-tightening functions, the auxiliary connecting seats to undertake the dynamic load equalization function, the positioning rings and retaining rings to achieve zero assembly offset, and the pressure plate protrusions and the reduced diameter water outlet holes to work together to form a pressure stabilizing cavity. The four components form an inseparable whole in terms of spatial layout, mechanical division of labor, and functional coupling. Actual tests show that this embodiment can maintain no leakage for 30 minutes under a static pressure of 1.8MPa, and after completing 100,000 fatigue tests under alternating water pressure of 10Hz / ±0.5MPa, the torque attenuation rate of all connecting screws is <2.1%, and the maximum gap between the shell and the water outlet panel is <0.03mm, which fully meets the explosion-proof safety level I requirements of GB / T 23444—2023 "Sanitary Ware Shower Heads".

[0035] This application features a cylindrical diverter extending from the connecting seat into the inner side of the housing. The diverter has four diverting holes spaced apart on its side, each connected to a connecting pipe, and these holes are distributed along a spiral line on the side of the diverter. While the diverter is made of ABS plastic, in practical applications it can also be made of 316L stainless steel or PPS engineering plastic; this application does not limit the specific materials used.

[0036] In a preferred embodiment, the number of main connectors is limited to 4 or 6, and the number of auxiliary connectors is 16 or 24. Specifically, a combination of 4 main connectors and 24 auxiliary connectors is used: the main connectors are evenly distributed along the four quadrants of the circumference (0°, 90°, 180°, 270°), with adjacent angles of 90°, and the center of the main connector hole is 36.0 mm from the center of the housing (radius R1). The auxiliary connectors are evenly distributed along the circumference at 15° intervals (24 points in total), with the center of the main connector hole 42.5 mm from the center of the housing (radius R2), located 6.5 mm outside the main connector ring. All main and auxiliary connectors are injection molded into the housing in one piece, with the mold cavity dimensional tolerance controlled within ±0.05 mm. The main and auxiliary connectors are synchronously stamped on the water outlet panel at the same angular relationship, with a positional error ≤0.1 mm. This layout ensures a sufficiently large spacing between the main connectors, facilitating visual alignment and rapid tightening.

[0037] In existing technologies, pressure plate protrusions are mostly cylindrical or conical. When mating with the positioning holes in the housing, they suffer from poor guidance, high insertion resistance, or unstable axial positioning, easily causing the pressure plate to tilt, leading to misalignment of the reduced-diameter outlet axis and deterioration of the throttling effect. To improve the mating accuracy and assembly reliability of the protrusion and positioning hole, this application specifies that the protrusion is frustum-shaped, with its large end flush with the bottom surface of the pressure plate and its small end extending into the positioning hole of the housing. The single-sided gap between the outer diameter of the small end and the inner diameter of the positioning hole is 0.05–0.15 mm. In a specific implementation, the large end diameter of the protrusion is Φ3.2 mm, the small end diameter is Φ1.6 mm, the cone angle is 12°, the height is 1.2 mm, and it is integrally injection molded with the pressure plate body using ABS plastic.

[0038] During assembly, the small end of the protrusion first enters the positioning hole, and the conical surface provides a self-guiding function. After it is in place, the gap between the bottom surface of the pressure plate and the inner wall of the housing is ≤0.02mm. This frustum-shaped structure has both guiding and positioning rigidity: the conical surface automatically corrects the angular deviation during the insertion stage, the small end forms a stable contact ring with the hole wall, and the large end is flush with the bottom surface of the pressure plate to avoid stress concentration.

[0039] In existing technologies, the pressurizing orifice and the outlet orifice often use the same or a simple scaled-down version, failing to balance flow requirements and pressure stabilization, easily leading to insufficient flow or excessive pressure fluctuations. To precisely control the throttling intensity and the pressure stabilizing chamber volume, this embodiment limits the ratio of the outlet orifice diameter to the pressurizing orifice diameter to d. 出水孔 / d 加压孔 =1:1.8–1:2.5.

[0040] In specific implementation, the diameter of the pressurizing hole is Φ3.2mm, the diameter of the outlet hole is Φ1.6mm, and the diameter reduction ratio is 1:2.0; the depth of the pressurizing hole is 1.0mm, the outlet hole penetrates the protrusion, and the coaxiality of the two holes is ensured by the injection mold (≤0.03mm); in practical applications, this diameter reduction ratio can also be adjusted to 1:1.8 (suitable for small flow household type) or 1:2.5 (suitable for large flow commercial type) according to the overall flow requirements, and this application embodiment does not limit this. This proportional design causes a controllable Venturi effect when the water flows through the diameter reduction section, forming a composite flow field in the pressurizing hole where the low-pressure backflow zone and the mainstream stable zone are superimposed, which not only suppresses the transmission of pressure pulsation, but also maintains sufficient water output, completely solving the contradiction in the traditional structure that "stabilizing pressure leads to reduced flow, and increasing flow leads to instability".

[0041] To enhance the stability and durability of the pre-positioning constraint, this application specifies that the positioning ring is an elastic rubber ring with a barb structure on its outer edge that is interference-fitted with the annular groove. The height of the barb is 0.3–0.6 mm, and the interference between the barb and the side wall of the groove is 0.1–0.2 mm. In specific implementation, the positioning ring is made of liquid silicone rubber LSR 4305, Shore A60, and is encapsulated on the back of the SUS304 water outlet panel through secondary injection molding; the barb is a single-sided right-angled trapezoidal structure with a height of 0.4mm, a top width of 0.25mm, a root width of 0.6mm, and a barb bevel angle of 12° to ensure that the assembly guide force is ≤15N; the annular groove is a die-cast feature of the shell, with a groove width of 1.6mm, a groove depth of 0.8mm, and a sidewall verticality of ≤0.05mm; the interference fit between the barb and the sidewall of the groove is set to 0.15mm, and after assembly, the root of the barb generates elastic compression, producing an axial constraint stiffness of 2.8N / mm; in practical applications, this barb structure can also be replaced by a double barb (symmetrical front and rear) or an elastic corrugated structure, which is not limited in this application embodiment. This design enables the positioning ring to establish an axial locking force of ≥8N and an anti-rotation torque of ≥0.5N·m in the early stage of assembly, ensuring that the water outlet panel does not shift during subsequent tightening. The alignment accuracy between the main / auxiliary connectors and the corresponding connecting holes reaches ±0.05mm, and the success rate of screws being screwed in on the first attempt is increased from 89% in conventional structures to 99.95%, eliminating the risk of shell cracking due to misalignment.

[0042] This application specifies that the positioning ring and the housing are integrally molded, or are fixedly connected to the housing by ultrasonic welding. In specific implementation, the integral molding scheme is preferred: the positioning ring and the housing are integrally injection molded from ABS plastic, with the mold parting surface located on the bottom surface of the positioning ring to eliminate stress concentration; the integral molding scheme ensures zero gap and zero thermal deformation difference between the positioning ring and the housing, and the long-term stability of the geometric accuracy of the slot.

[0043] In another embodiment, to strengthen the axial constraint of the pressure plate, this application specifies that an auxiliary fastening structure is provided between the pressure plate and the water outlet panel. The auxiliary fastening structure is an elastic buckle set on the edge of the pressure plate and extending towards the water outlet panel. In specific implementation, the elastic buckle is integrally injection molded from POM material onto the outer edge of the pressure plate, with a total of 4 buckles, evenly distributed at 0°, 90°, 180°, and 270° positions around the circumference of the pressure plate. The buckle has a cantilever beam structure with a root thickness of 0.8 mm, a free length of 2.5 mm, and a 0.3 mm spherical protrusion at the front end. The water outlet panel has a corresponding Φ2.2 mm circular locking hole. After the buckle is inserted, the spherical protrusion engages in the hole to form a 0.15 mm interference fit. In practical applications, this auxiliary fastening structure can also be replaced by a through-type M2.5 screw (with a spring washer), which is not limited in this embodiment. The elastic buckle and the protrusion form a "dual constraint mechanism": the protrusion is responsible for precise radial and axial positioning, while the buckle is responsible for resisting axial disengagement and circumferential micro-rotation. The two work together to ensure that the water output stability meets the standards in the long term.

[0044] This application provides a method for assembling an explosion-proof top sprayer, comprising the following steps:

[0045] S1. Insert each protrusion of the pressure plate into the corresponding positioning hole on the housing to complete the axial and radial positioning of the pressure plate;

[0046] S2. Cover the water outlet panel onto the housing, so that the positioning ring is embedded in the annular groove of the positioning ring, forming a pre-positioning constraint for assembly;

[0047] S3. Synchronously align the main connector with the main connecting hole and the auxiliary connector with the auxiliary connecting hole;

[0048] S4. Using a torque-controllable tool, tighten the fasteners in a diagonal cyclical manner, first tightening the main connecting seat and then tightening the auxiliary connecting seat, until the main connecting seat and the auxiliary connecting seat reach the preset tightening torque of 1.2–1.8 N·m simultaneously, thereby rigidly connecting the shell and the water outlet panel into one unit. In this embodiment, screws are selected as the fasteners, but other common fasteners such as bolts can also be used, and it is not limited to this.

[0049] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An explosion-proof top spray, comprising a water outlet body and a water inlet pipe connected to the water outlet body via a connecting seat (11), the water outlet body comprising a housing (10) and a water outlet panel (20) connected to the housing (10) via an explosion-proof connection structure, the housing (10) having a U-shaped structure and a circular cross-section, characterized in that: The explosion-proof connection structure includes a main connecting ring, an auxiliary connecting ring, a positioning ring (14), and a pressure plate (21). The main connecting ring is located inside the housing (10) and consists of 2–8 main connecting seats (12) spaced apart along the circumferential direction. Each main connecting seat (12) has a main connecting hole (121) on its top. The auxiliary connecting ring is located radially outside the main connecting ring and consists of 12–30 auxiliary connecting seats (13) spaced apart along the circumferential direction. Each auxiliary connecting seat (13) has an auxiliary connecting hole (131). The positioning ring (14) is located between the main connecting ring and the auxiliary connecting ring and inside the housing (10). Its top is provided with a main connecting hole (131). The water outlet panel (20) has an annular groove; the back of the water outlet panel (20) is provided with a main connector (22) that matches the main connection hole (121), an auxiliary connector (23) that matches the auxiliary connection hole (131), and a positioning ring (24) located between the two. The positioning ring (24) cooperates with the annular groove to provide pre-positioning constraints for assembly; the housing (10) is provided with a main mounting hole and an auxiliary mounting hole for fasteners to pass through, so that the main connector (22) and the main connection hole (121) and the auxiliary connector (23) and the auxiliary connection hole (131) are respectively locked by fasteners, thereby rigidly connecting the housing (10) and the water outlet panel (20) into one unit.

2. A flame arrestant roof vent according to claim 1, characterised in that: The pressure plate (21) is sandwiched between the housing (10) and the water outlet panel (20) and is located inside the positioning ring (24). It has multiple pressure holes, and each pressure hole has an integrally formed protrusion at the bottom. The protrusion is inserted into the corresponding positioning hole on the housing (10). The protrusion has a water outlet hole that communicates with the pressure hole, and the diameter of the water outlet hole is smaller than the diameter of the pressure hole. Together, they form an integrated throttling and pressure stabilizing positioning unit.

3. The explosion-proof roof vent of claim 1, wherein: The connecting seat (11) extends to the inner side of the housing (10) to form a cylindrical diverter (111). The diverter (111) has 4–12 diverter holes (1111) spaced apart on its side, which are connected to the connecting pipe. The diverter holes (1111) are distributed along a spiral line on the side of the diverter (111).

4. The explosion-proof roof vent of claim 1, wherein: The number of main connectors (12) is 4 or 6, and the number of auxiliary connectors (13) is 16 or 24.

5. The explosion-proof top spray according to claim 2, characterized in that: The protrusion is frustum-shaped, with its large end flush with the bottom surface of the pressure plate (21) and its small end extending into the positioning hole of the housing (10). The single-sided gap between the outer diameter of the small end and the inner diameter of the positioning hole is 0.05–0.15 mm.

6. The explosion-proof top spray according to claim 2, characterized in that: The ratio of the diameter of the water outlet to the diameter of the pressurization hole is d_water_outlet / d_pressurization_hole = 1:1.8–1:2.

5.

7. The explosion-proof top spray according to claim 1, characterized in that: The positioning ring (24) is an elastic rubber ring with a barb structure on its outer edge that is interference-fitted with the annular groove. The height of the barb is 0.3–0.6 mm, and the interference between the barb and the side wall of the groove is 0.1–0.2 mm.

8. The explosion-proof top spray according to claim 1, characterized in that: The positioning ring (14) is integrally formed with the shell (10), or is fixedly connected to the shell (10) by ultrasonic welding.

9. The explosion-proof top spray according to claim 1, characterized in that: An auxiliary fastening structure is provided between the pressure plate (21) and the water outlet panel (20). The auxiliary fastening structure is an elastic buckle that is set on the edge of the pressure plate (21) and extends toward the water outlet panel (20).

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