Pressure reducer and air respirator

Abstract

This invention discloses a pressure reducer and an air respirator. The pressure reducer includes: a housing having a first end and a second end; a piston movably disposed within the housing along a first direction and elastically connected to the first end of the housing; a partition structure fixed within the housing and located between the piston and the second end of the housing, forming a second chamber between the partition structure and the piston, and a first chamber between the partition structure and the second end of the housing; the partition structure has a flow hole connecting the two chambers, the first chamber being used to communicate with an air source, and the second chamber being used to output gas; and a sealing part, at least partially disposed within the first chamber and connected to the piston, its position corresponding to the flow hole, and the sealing part having a pressure-bearing surface for bearing the gas pressure within the first chamber. This invention, by integrating the piston, sealing part, and chambers within the housing, achieves an increase in output pressure as the air source pressure decreases, providing a pressure trigger signal for a frequency converter alarm system, simplifying the structure, and improving reliability.

Description

Technical Field

[0001] This invention relates to the field of respiratory protection equipment technology, specifically to a pressure reducer and an air respirator. Background Technology

[0002] An air respirator is an essential personal protective equipment for firefighters, rescue workers, and others operating in oxygen-deficient or toxic gas environments. Its function is to provide the user with clean and safe breathing air. A typical air respirator usually includes: an air cylinder, a pressure reducer, an air supply valve, and a face mask. The air cylinder stores high-pressure air, typically with an output pressure of 30 MPa. The pressure reducer is connected to the cylinder and reduces the high-pressure gas to a medium pressure (0.5 MPa-1.0 MPa). The air supply valve is connected between the pressure reducer and the face mask, reducing the medium pressure output to a suitable breathing pressure, generally not exceeding 1 kPa. The face mask is designed to fit snugly against the user's face.

[0003] Given the extremely hazardous environment in which self-contained breathing apparatus (SCBA) are used, it is necessary to promptly alert the user to evacuate when the gas pressure in the cylinder drops to a safe margin. One related technology employs a dual-redundant pressure regulator structure to implement a low-pressure alarm, comprising a primary pressure regulator and a secondary pressure regulator connected in parallel. Under normal operating conditions, the primary pressure regulator supplies air, maintaining the output pressure within a lower normal operating pressure range. When the gas source pressure drops to a predetermined threshold or the primary pressure regulator malfunctions, the system automatically switches to the secondary pressure regulator, causing the output pressure to jump to a higher secondary pressure. This increased pressure triggers the alarm system, thus alerting the user that the gas supply is about to run out.

[0004] However, the aforementioned technical solutions employ two independent pressure reducers for pressure switching, resulting in a complex internal structure, an increased number of components, and consequently higher material and assembly costs. This also complicates the production and assembly process, reducing production efficiency. Furthermore, the complex structure introduces more potential failure points, impacting the long-term reliability of the entire machine and leading to difficulties in fault location and maintenance during later maintenance, thus increasing the overall lifecycle maintenance costs of the equipment. Summary of the Invention

[0005] The present invention aims to at least solve the problems of complex structure and poor maintainability caused by the use of dual pressure reducers in the prior art, and proposes a pressure reducer and an air breathing apparatus.

[0006] To achieve the objectives of this invention, according to one aspect of the invention, a pressure reducer is provided, comprising: a housing having a first end and a second end along a first direction; a piston movably disposed within the housing along the first direction, and elastically connected to the first end of the housing; a partition structure fixedly disposed within the housing and located between the piston and the second end of the housing, wherein a second chamber is formed between the partition structure and the piston, and a first chamber is formed between the partition structure and the second end of the housing, the partition structure having a flow hole connecting the first chamber and the second chamber, the first chamber being for communication with a gas source, and the second chamber being for outputting gas; and a sealing portion at least partially disposed within the first chamber and connected to the piston, the position of the sealing portion corresponding to the flow hole, the sealing portion moving with the piston to move relative to the flow hole, thereby opening or closing the flow hole, wherein the portion of the sealing portion within the first chamber has a pressure-bearing surface to withstand pressure and transmit the force to the piston.

[0007] In some embodiments, the partition structure is a partition plate fixedly disposed within the housing, and the flow hole is disposed on the partition plate.

[0008] In some embodiments, the sealing portion has a first end and a second end along the first direction, the first end of the sealing portion is connected to the piston, the second end of the sealing portion is away from the piston, and the end face of the second end of the sealing portion forms the pressure-bearing surface.

[0009] In some embodiments, the sealing portion is a frustum or a sphere.

[0010] In some embodiments, the pressure reducer further includes an elastic element disposed between the piston and a first end of the housing.

[0011] In some embodiments, the piston has a piston surface facing the second chamber, the area of ​​the piston surface is S1, the area of ​​the flow orifice is S2, and the range of S1 / S2 is 20≤S1 / S2≤200.

[0012] In some embodiments, the flow hole is a circular through hole.

[0013] In some embodiments, the blocking part forms a flow channel with the flow hole when it moves, and the flow area of ​​the flow channel changes linearly with the movement of the blocking part.

[0014] In some embodiments, the sealing part is a frustum with a sloping side, and the sloping side forms the flow channel between the flow channel and the inner wall of the flow hole.

[0015] In some embodiments, the blocking part forms a flow channel with the flow hole when it moves, and the flow area of ​​the flow channel changes non-linearly with the movement of the blocking part.

[0016] In some embodiments, the sealing part is a sphere, and the spherical surface forms the flow channel between the sphere and the inner wall of the flow hole.

[0017] In some embodiments, the pressure reducer further includes: an adjusting rod, which passes through the housing and is slidably and sealingly connected to the housing, one end of the adjusting rod being located inside the first chamber and rigidly connected to the sealing portion, and the other end being located outside the housing.

[0018] In some embodiments, the housing is provided with a mounting hole communicating with the outside, the adjusting rod passes through the mounting hole, the area of ​​the flow passage is S2, the area of ​​the mounting hole is S3, and the range of S3 / S2 is 0. <S3 / S2≤1。

[0019] In some embodiments, the piston has a piston surface facing the second chamber, the area of ​​the piston surface being S1, and the range of S1 / S2 being 20≤S1 / S2≤200.

[0020] According to another aspect of the invention, an air respirator is also disclosed, comprising the aforementioned pressure reducer.

[0021] In some embodiments, the air respirator further includes: a mask; an air source in communication with a first chamber of the pressure reducer; and an alarm system in communication with a second chamber of the pressure reducer, which is triggered when the output pressure of the second chamber reaches a preset threshold, and the alarm frequency of the alarm system increases accordingly as the output pressure increases.

[0022] In some embodiments, the piston has a piston surface facing the second chamber, the area of ​​the piston surface is S1, the area of ​​the flow orifice is S2, and the range of S1 / S2 is 20≤S1 / S2≤100.

[0023] In some embodiments, the air respirator further includes: a mask; an air source; and a first connecting tube, one end of which is connected to the second chamber of the pressure reducer and the other end of which is connected to an air supply valve.

[0024] The pressure regulator of this invention integrates a piston, a sealing part, a first chamber, and a second chamber within a housing. Through the cooperation of these components, the output pressure automatically increases as the gas source pressure decreases, eliminating the need for two separate pressure regulators. This structure reduces the number of parts, lowers material costs and assembly processes, while also reducing potential failure points and improving overall reliability.

[0025] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the pressure reducer according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the pressure reducer in the open state according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram showing the relationship between the area of ​​the piston surface and the area of ​​the flow passage of the pressure reducer according to an embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of the pressure reducer according to another embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the pressure reducer in the open state according to another embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram showing the relationship between the area of ​​the piston surface, the area of ​​the flow passage, and the area of ​​the mounting hole of the pressure reducer according to another embodiment of the present invention.

[0032] Figure 7 This is a schematic diagram of the pressure reducer according to another embodiment of the present invention;

[0033] Figure 8 This is a schematic diagram of the structure of an air respirator according to an embodiment of the present invention;

[0034] Figure 9 This is a schematic diagram of the alarm system of an air respirator according to an embodiment of the present invention;

[0035] Figure 10 This is a schematic diagram of the structure of an air respirator according to another embodiment of the present invention;

[0036] List of reference numerals in the attached diagram:

[0037] 10. Housing; 11. Mounting hole; 20. Piston; 21. Piston face; 30. Sealing part; 31. Pressure bearing surface; 40. Piston rod; 50. Elastic element; 60. Partition; 61. Flow hole; 81. First chamber; 82. Second chamber; 90. Adjusting rod; 91. Transverse section; 92. Longitudinal section; 100. Mask; 200. Air source; 300. Pressure reducer; 400. Alarm system; 401. Outer shell; 402. Vibration pin; 403. Return spring; 404. Vibration element; 405. Pneumatic chamber; 406. Air inlet channel; 407. Air inlet; 408. Air outlet; 500. First connecting pipe; 600. Air supply valve; 700. Exhaust valve. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solution of the present invention, the pressure reducer and air respirator provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0039] Using two independent pressure regulators for pressure switching complicates the system's internal structure and increases the number of components. This not only introduces more potential failure points, affecting the long-term reliability of the entire machine, but also significantly increases material costs, assembly costs, and quality control costs. Furthermore, it complicates the production and assembly process, reducing production efficiency.

[0040] Secondly, and more importantly, the alarm information provided by this solution is rather limited. The alarm system is triggered when the gas pressure drops to a predetermined threshold, but the intensity or frequency of the alarm signal remains essentially constant regardless of changes in the remaining gas supply. Users can only receive the single-point information that "the warning line has been reached," without being able to perceive the specific amount of remaining gas or its rate of decay. This makes it difficult to scientifically plan evacuation schedules, adjust operational tasks, or determine the remaining usable time based on the gas supply's decay.

[0041] In high-risk operational scenarios such as firefighting and rescue operations, this lack of information can pose safety hazards. For example, if users cannot determine whether the gas level has just reached the warning limit or is about to run out completely when they hear an alarm, it may affect the accuracy of their evacuation decisions and even delay the best evacuation opportunity.

[0042] To solve the above problems, such as Figure 1 and Figure 2 As shown, this invention discloses a pressure reducer that can be applied to an air respirator. This air respirator typically includes a back frame and harness assembly, a cylinder for storing compressed air and a cylinder valve, a pressure reducer mounted on the back frame, an air supply valve mounted on the face mask, and a head harness for securing the face mask to the user's face. The cylinder is used to store and deliver compressed air, and the cylinder valve is used to control the opening and closing of the cylinder.

[0043] The pressure reducer includes a housing 10, a piston 20, a partition structure, and a sealing part 30. The housing 10 has a first end (the upper end of the housing 10 in the figure) and a second end (the lower end of the housing 10 in the figure) along a first direction. The piston 20 is movably disposed within the housing 10 along the first direction, and is elastically connected to the first end of the housing 10. The partition structure is fixedly disposed within the housing 10 and located between the piston 20 and the second end of the housing 10. A second chamber 82 is formed between the partition structure and the piston 20, and a first chamber 81 is formed between the partition structure and the second end of the housing 10. The partition structure has a connection between the first chamber 81 and the second end of the housing 10. The chamber 82 has a flow-through orifice 61. The first chamber 81 is used to communicate with a gas source (e.g., a gas cylinder), and the second chamber 82 is used to output gas. The gas pressure in the second chamber 82 is lower than the gas pressure in the first chamber 81. The sealing part 30 is at least partially disposed in the first chamber 81 and connected to the piston 20. The position of the sealing part 30 corresponds to the flow-through orifice 61. The sealing part 30 moves with the piston 20 to move relative to the flow-through orifice 61, thereby opening or closing the flow-through orifice 61. The portion of the sealing part 30 located in the first chamber 81 is provided with a pressure-bearing surface 31 to withstand pressure and transmit the force to the piston 20.

[0044] like Figure 1 As shown, when the sealing part 30 closes the flow hole 61, the piston 20 of the pressure reducer is in a state of force equilibrium. At this time, the piston 20 is subjected to three forces in the first direction: an elastic force Fs generated by the elastic connection and applied to the piston 20, which is directed toward the second end of the housing 10; an effective force Fm exerted by the gas in the second chamber 82 on the piston 20, which is directed toward the first end of the housing 10; and an effective force Fh exerted by the gas in the first chamber 81 on the sealing part 30, which is transmitted to the piston 20 through the connection between the sealing part 30 and the piston 20, and is directed toward the first end of the housing 10. Therefore, the equilibrium relationship satisfies: Fs = Fm + Fh (Equation 1).

[0045] For ease of description, in this article:

[0046] Pm represents the gas pressure in the second chamber 82 of the pressure reducer, that is, the output pressure or medium-pressure gas pressure of the pressure reducer;

[0047] Ph represents the gas pressure in the first chamber 81 of the pressure reducer, i.e., the gas source pressure or high-pressure gas pressure.

[0048] Medium-pressure gas specifically refers to a gas medium with a pressure of Pm, that is, the gas in the second chamber 82 of the pressure reducer; high-pressure gas specifically refers to a medium with a pressure of Ph, that is, the gas in the first chamber 81 of the pressure reducer or the gas source.

[0049] Based on the relationship between pressure and effective area, we can obtain: Fm = Pm × Sm (Equation 2), Fh = Ph × Sh (Equation 3). Where Pm is the gas pressure in the second chamber 82, and Sm is the effective area of ​​the piston 20 subjected to the gas in the second chamber 82, which is the effective area of ​​the medium-pressure gas in the second chamber 82 acting on the piston 20. Ph is the gas pressure in the first chamber 81, and Sh is the effective area of ​​the sealing part 30 subjected to the gas in the first chamber 81, which is the effective area of ​​the high-pressure gas in the first chamber 81 acting on the pressure-bearing surface 31.

[0050] When the breathing mask connected to the second chamber 82 inhales, the gas in the second chamber 82 decreases, causing Pm to decrease. According to Equation 2, with Sm constant, when Pm decreases, Fm decreases, resulting in Fm + Fh being less than Fs. At this time, as... Figure 2 As shown, piston 20 moves towards the second end of housing 10. The movement of piston 20, through its connection with the sealing part 30, causes the sealing part 30 to move synchronously, gradually moving it away from the flow orifice 61, thus opening the flow orifice 61. When the flow orifice 61 is open, because the air pressure in the second chamber 82 is lower than that in the first chamber 81, the high-pressure gas in the first chamber 81 enters the second chamber 82 through the flow orifice 61, causing Pm to rise. Similarly, with Sm unchanged, the rise in Pm increases Fm, causing piston 20 to move towards the first end of housing 10, driving the sealing part 30 to gradually approach the flow orifice 61, reducing the opening of the flow orifice 61 until the sealing part 30 closes the flow orifice 61 again, thus bringing piston 20 back into a state of force equilibrium and completing one cycle. This process repeats continuously during breathing, achieving continuous air supply.

[0051] When piston 20 is in equilibrium, the position of piston 20 remains unchanged because the flow hole 61 is closed. Therefore, the elastic force Fs it experiences remains unchanged. As the gas source is consumed, the gas pressure Ph in the first chamber 81 gradually decreases. According to Equation 3, when Sh remains constant, the decrease in Ph causes Fh to decrease. After Fh decreases, in order to maintain the equilibrium state of piston 20, Fm needs to increase. According to Equation 2, when Sm remains constant, if Fm needs to increase, it means that Pm also needs to increase. Therefore, with the pressure reducer using the above structure, after the gas source pressure Ph decreases, the output pressure Pm of the pressure reducer will automatically increase as the gas source pressure Ph decreases. When Ph decreases to a certain level, Pm reaches the alarm system activation threshold, which will trigger the alarm system, thereby reminding the user that the gas source is about to run out.

[0052] In the combined cyclic process, after the gas source pressure Ph decreases, during the reciprocating cycle of piston 20, more high-pressure gas is needed to enter the second chamber 82 to achieve balance, thereby increasing Pm until a new balance is reached. As Ph continues to decrease, the above process occurs cyclically, causing Pm to continuously increase. When Ph decreases to a certain level, Pm reaches the alarm system activation threshold, thereby triggering the alarm system.

[0053] The pressure regulator of the present invention integrates a piston 20, a sealing part 30, a first chamber 81, and a second chamber 82 within a housing 10. Through the cooperation of these components, the output pressure automatically increases as the gas source pressure decreases, eliminating the need for two separate pressure regulators. This structure reduces the number of parts, lowers material costs and assembly processes, while also reducing potential failure points and improving overall reliability.

[0054] Furthermore, in some embodiments, Pm and Ph are typically monotonic. In this case, Pm can continuously increase as Ph decreases. When Pm reaches the alarm system activation threshold, Pm continues to increase as Ph further decreases, and the alarm frequency of the alarm system increases accordingly, so that users can judge the decay of remaining gas volume by the trend of alarm frequency changes.

[0055] The structure of the pressure reducer of the present invention will be further described below with reference to specific embodiments.

[0056] In some embodiments, the partition structure is a partition 60 fixedly disposed within the housing 10. The partition 60 is fixedly disposed within the housing 10 and located between the piston 20 and the second end of the housing 10; wherein a second chamber 82 is formed between the partition 60 and the piston 20, and a first chamber 81 is formed between the partition 60 and the second end of the housing 10; a flow-through hole 61 is provided on the partition 60. In other words, a partition 60 is also disposed inside the housing 10, fixedly disposed within the housing 10, and located between the piston 20 and the second end of the housing 10. A second chamber 82 is formed between the partition 60 and the piston 20, and a first chamber 81 is formed between the partition 60 and the second end of the housing 10; a flow-through hole 61 is provided on the partition 60. The structure of the partition 60 clearly separates the first chamber 81 and the second chamber 82, allowing communication only through the flow-through hole 61.

[0057] It should be noted that the partition 60 and the housing 10 can be fixed and sealed in various ways: as a preferred embodiment, the partition 60 and the housing 10 are integrally formed to ensure structural strength, simplify assembly and ensure airtightness; in other embodiments, the partition 60 can be fixed to the inner wall of the housing 10 by interference fit, welding, threaded connection or snap-fit, and a sealing element is provided at the connection to ensure airtight isolation between the first chamber 81 and the second chamber 82 and prevent gas leakage.

[0058] In some embodiments, the flow passage 61 may be a circular through-hole structure. Circular through-holes are easy to manufacture and can form a good fit with the sealing portion 30, achieving reliable opening and closing functions.

[0059] For example, the diameter of the flow hole 61 ranges from 3.5 mm to 5.5 mm.

[0060] In some embodiments, the sealing portion 30 has a first end and a second end along a first direction. The first end of the sealing portion 30 is connected to the piston 20, and the second end of the sealing portion 30 is away from the piston 20. The end face of the second end of the sealing portion 30 forms a pressure-bearing surface 31. Specifically, the sealing portion 30 has a first end and a second end along the axial direction of the piston 20. The first end is connected to the piston 20 via a piston rod 40, and the second end is away from the piston 20. The end face of the second end of the sealing portion 30 forms a pressure-bearing surface 31. The piston rod 40 extends axially, with one end fixedly connected to the piston 20 and the other end fixedly connected to the first end of the sealing portion 30. The piston rod 40 is movably inserted into the flow hole 61. This arrangement allows the pressure-bearing surface 31 of the sealing portion 30 to directly withstand the gas pressure inside the first chamber 81. This pressure is transmitted through the sealing portion 30 to the piston rod 40, and then through the piston rod 40 to the piston 20.

[0061] For example, the blocking part 30 can be a body of revolution, such as a frustum, a sphere, etc. It can also be a cuboid or other shapes, and is not limited in this embodiment.

[0062] When the sealing part 30 is a frustum, its side is an inclined plane. Since the angle of the inclined plane is fixed, the moving distance of the sealing part 30 is linearly related to the flow area of ​​the flow channel, thus causing a linear change in the gas flow rate entering the second chamber 82 and a smooth output pressure regulation process. Specifically, the piston rod 40 can be coaxially arranged with the flow hole 61, and the sealing part 30 is fixed to the end of the piston rod 40 and kept coaxially aligned with the flow hole 61. When the piston 20 moves due to unbalanced force, the piston 20 drives the piston rod 40 to move synchronously along the axial direction, and the piston rod 40 drives the sealing part 30 at its end to move synchronously. Under the action of the piston rod 40, a flow channel is formed between the inclined plane of the sealing part 30 and the inner wall of the flow hole 61. Since the angle of the inclined plane is fixed, the moving distance of the sealing part 30 is linearly related to the flow area of ​​the flow channel, thus causing a linear change in the gas flow rate entering the second chamber 82 and a smooth output pressure regulation process.

[0063] For example, the angle between the inclined surface of the frustum and its axis ranges from 25° to 45°. In some preferred embodiments, for example, the angle between the inclined surface of the frustum and its axis can be 30° or 40°.

[0064] In the above embodiment, the sealing part 30 is a frustum, but this is not limiting. In another optional embodiment, the sealing part 30 can be a sphere. When the sealing part 30 is a sphere, its spherical surface forms a flow channel with the inner wall of the flow hole 61. The piston rod 40 is coaxially arranged with the flow hole 61, and the sealing part 30 is fixed to the end of the piston rod 40 and kept coaxially aligned with the flow hole 61. When the piston 20 moves due to unbalanced force, the piston 20 drives the piston rod 40 to move synchronously along the axial direction, and the piston rod 40 drives the sealing part 30 at its end to move synchronously. Driven by the piston rod 40, a flow channel is formed between the spherical surface of the sealing part 30 and the inner wall of the flow passage 61. Due to the change in the curvature of the spherical surface, there is a non-linear relationship between the moving distance of the sealing part 30 and the flow area of ​​the flow passage, which causes the gas flow rate entering the second chamber 82 to change non-linearly. In other words, when the sealing part 30 opens the flow passage 61 by moving, with the moving distance of the sealing part 30 remaining unchanged, the flow cross-sectional area of ​​the flow passage is larger and the gas flow rate is larger due to the change in the curvature of the spherical surface. Therefore, the pressure reducer has a faster response speed and can be used in application scenarios that require rapid response or specific pressure curves.

[0065] In some embodiments, the pressure reducer further includes an elastic element 50. The elastic element 50 is disposed between the piston 20 and the first end of the housing 10. In other words, an elastic element 50 is disposed between the piston 20 and the first end of the housing 10. The elastic element 50 may specifically be one of a spring, an elastic sheet, or an elastic body, used to achieve an elastic connection between the piston 20 and the first end of the housing 10 and to provide the required elastic force Fs. In some embodiments, the elastic element 50 is a helical spring with a stiffness coefficient of 100,000 N / m to 200,000 N / m.

[0066] It is understandable that by adjusting the effective area (Sh or Sm) of the gas interaction in the first chamber 81 and the second chamber 82, the output range of Pm can be adjusted. Specifically, substituting Equations 2 and 3 into Equation 1 yields: Fs = (Pm × Sm) + (Ph × Sh), which, after transformation, gives Pm = [Fs - (Ph × Sh)] / Sm (Equation 4). Equation 4 shows that, with the elastic force Fs unchanged, increasing Sm or decreasing Sh will decrease the output Pm while maintaining the same Ph; conversely, decreasing Sm or increasing Sh will increase the output Pm while maintaining the same Ph.

[0067] It should be noted that, as mentioned earlier, Sm is the effective area of ​​the medium-pressure gas in the second chamber 82 acting on the piston 20, which is not the same as the area S1 of the piston surface 21 of the piston 20. Similarly, Sh is the effective area of ​​the high-pressure gas in the first chamber 81 acting on the pressure-bearing surface 31, which is not the same as the area of ​​the pressure-bearing surface 31, but is related to the area S2 of the flow passage 61.

[0068] Specifically, in some embodiments, the piston 20 has a piston surface 21 facing the second chamber 82, the area of ​​the piston surface 21 being S1, and the area of ​​the flow passage 61 being S2, such as... Figure 3 As shown, in the balanced state of piston 20, due to the presence of flow orifice 61, a projection area A is formed on piston surface 21 and a projection area B is formed on pressure bearing surface 31. Within projection area A, the end of sealing part 30 facing piston 20, that is, the first end of sealing part 30, is located in the second chamber 82. Since this position is also exposed in the second chamber 82, it is also subjected to the action of medium-pressure gas in the second chamber 82. Moreover, the force exerted by the medium-pressure gas on sealing part 30 is opposite in direction to the force exerted by the medium-pressure gas on piston surface 21. Since sealing part 30 is connected to piston 20, it will offset part of the force exerted by medium-pressure gas on piston surface 21. Therefore, the effective area of ​​piston 20 subjected to the action of medium-pressure gas in the second chamber 82, that is, the effective area Sm of the medium-pressure gas in the second chamber 82 exerting force on piston 20, needs to be reduced by the area of ​​the offset part based on piston surface 21. This part of the area is exactly the area S2 of the flow hole 61. Therefore, Sm = S1 - S2 (Equation 5).

[0069] Similarly, Sh is the effective area of ​​the sealing part 30 subjected to the gas in the first chamber 81, that is, the effective area of ​​the high-pressure gas in the first chamber 81 acting on the sealing part 30. Specifically, with Figure 4 Taking the frustum-shaped sealing part 30 as an example, the first end of the sealing part 30 facing the piston 20 is not only used to connect the piston rod 40, but the outer peripheral wall of the sealing part 30 near the first end also needs to abut against the inner peripheral wall of the flow hole 61 to achieve the sealing of the flow hole 61. Therefore, the area S4 of the pressure bearing surface 31 of the sealing part 30 cannot be less than the area of ​​the projection area B of the flow hole 61 on the pressure bearing surface 31, that is, the area S2 of the flow hole 61, i.e., S4≥S2.

[0070] When the sealing part 30 seals the flow hole 61, the pressure-bearing surface 31 is completely located inside the first chamber 81, and therefore will be subjected to the action of high-pressure gas. The first end of the sealing part 30 is located inside the projection area A, and the other end is located outside the projection area A. The part located inside the projection area A enters the flow hole 61 to abut against the inner peripheral wall of the flow hole 61, thereby sealing the flow hole 61, while the part entering the flow hole 61 is not subjected to the action of high-pressure gas from the first chamber 81. The portion of the first end of the sealing part 30 located outside the projection area A, since it does not enter the flow hole 61 but is located in the first chamber 81, will be subjected to the action of high-pressure gas in the first chamber 81, thereby generating a component force that drives the sealing part 30 to move toward the second end of the housing 10. This component force will offset part of the force acting on the pressure-bearing surface 31. Therefore, in this embodiment, the effective area Sh of the sealing part 30 subjected to the gas in the first chamber 81 is actually the area S2 of the flow hole 61, that is, Sh = S2 (Equation 6).

[0071] Therefore, substituting Equations 5 and 6 into Equation 4, we can obtain Pm = [Fs - (Ph × S2)] / (S1 - S2) (Equation 7). Equation 7 shows that when the elastic forces Fs, Ph, and S2 remain unchanged, if S1 is increased, the numerator in Equation 7 remains unchanged but the denominator increases, which can reduce the output Pm; conversely, if S1 is decreased, the numerator in Equation 7 remains unchanged but the denominator decreases, which can increase the output Pm.

[0072] By transforming Equation 7 through mathematical identity, we can obtain Pm = Ph + [Fs - (Ph × S1)] / (S1 - S2) (Equation 8), where, since Pm<Ph,S1> Therefore, we can deduce that Fs-(Ph×S1)<0 in Equation 8. Based on the above conditions, if the elastic forces Fs, Ph, and S1 remain unchanged, and S2 is increased, the numerator of [Fs-(Ph×S1)] / (S1-S2) remains unchanged but the denominator decreases, and its absolute value increases. However, since [Fs-(Ph×S1)] / (S1-S2)<0, [Fs-(Ph×S1)] / (S1-S2) will decrease, thus causing Pm to decrease. Conversely, if S2 is decreased, [Fs-(Ph×S1)] / (S1-S2) will increase, thus causing Pm to increase.

[0073] In some embodiments, the range of S1 / S2 is 20 ≤ S1 / S2 ≤ 200. Within this range, the increase curve of output pressure Pm as the gas source pressure Ph decreases has a suitable slope and linearity, which can keep the output pressure within a suitable range. As a further preferred embodiment, the range of S1 / S2 is 20 ≤ S1 / S2 ≤ 100. Within this range, as Ph decreases, the change in Pm is larger, thus obtaining a more suitable slope and linearity for linear pressure rise characteristics, which is convenient for matching with alarm systems of different specifications.

[0074] It should be noted that in the above embodiments, Pm can be adjusted by regulating the ratio between the flow orifice 61 and the piston surface 21. However, in some embodiments, if a more gradual change in Pm is desired, only the area S2 of the flow orifice 61 or the area S1 of the piston surface 21 can be adjusted. Reducing the area S2 of the flow orifice 61 will result in a smaller flow rate, affecting the medium-pressure output. Increasing the area S1 of the piston surface 21 will result in a larger piston, thereby increasing the volume of the pressure regulator.

[0075] Therefore, in order to solve the above-mentioned technical problems, in such Figures 4 to 7 In other embodiments of the invention shown, a pressure reducer is also disclosed, which is related to... Figure 1 and Figure 2 The pressure reducers shown are basically the same in structure, the difference being that... Figures 4 to 7 In the embodiment shown, the pressure reducer further includes an adjusting rod 90, which passes through the housing 10 and is slidably and sealingly connected to the housing 10. One end of the adjusting rod 90 is located inside the first chamber 81 and is rigidly connected to the sealing part 30, while the other end is located outside the housing 10.

[0076] Since the other end of the adjusting rod 90 is located outside the housing 10, it will not be affected by the high-pressure gas in the first chamber 81. By rigidly connecting the adjusting rod 90 to the sealing part 30 in the first chamber 81 (e.g., welding, snap-fit, bolt connection, etc.), the effective area of ​​the high-pressure gas in the first chamber 81 acting on the sealing part 30 is reduced. Thus, the degree of change of Pm can be adjusted without changing S2 or S1, so that the change of Pm is more gradual.

[0077] For example, such as Figures 4 to 6 As shown, the adjusting rod 90 is a straight rod, with one end connected to the pressure-bearing surface 31 and the other end extending to the outside of the housing 10. Its axis is coaxial with the piston rod 40. When the adjusting rod 90 is rigidly connected to the pressure-bearing surface 31, the end of the adjusting rod 90 connected to the pressure-bearing surface 31 occupies a portion of the area of ​​the pressure-bearing surface 31, preventing the high-pressure gas in the first chamber 81 from acting on that area. Similarly, the other end of the adjusting rod 90 is located outside the housing 10, preventing the high-pressure gas in the first chamber 81 from acting on it. Therefore, it effectively reduces the area of ​​the high-pressure gas acting on the sealing part 30. Thus, without changing the area of ​​the flow hole 61 and the piston surface 21, the change in Pm can be made more gradual by increasing the adjusting rod 90. When the forces are balanced, the new force balance relationship is: Fs = Fm + Fh - Fx (Equation 9), where Fx = Ph × S3 (Equation 10), and S3 is the area of ​​the mounting hole 11.

[0078] Specifically, the housing 10 is provided with an installation hole 11 communicating with the outside. The adjusting rod 90 is inserted into the installation hole 11, and the installation hole 11 and the adjusting rod 90 are matched. When the adjusting rod 90 is a straight rod, its outer diameter is equivalent to the inner diameter of the installation hole 11.

[0079] Therefore, substituting Equation 2, Equation 3, and Equation 10 into Equation 9, we can obtain: Fs = (Pm × Sm) + (Ph × Sh) - (Ph × S3). After transformation, we can get Pm = [Fs - (Ph × Sh) + (Ph × S3)] / Sm (Equation 11). From Equation 11, it can be seen that when the elastic force Fs, Sm, and Sh remain unchanged, if S3 is increased, the output Pm can be increased under the same Ph; conversely, if Sm is decreased, the output Pm can be decreased under the same Ph.

[0080] In some embodiments, the range of S3 / S2 is 0 < S3 / S2 ≤ 1. By adjusting and increasing the adjusting rod 90, the effective acting area of the high-pressure gas on the sealing portion 30 can be effectively adjusted, which is more conducive to the adjustment of Pm, and thus it is easier to make the change degree of Pm meet the expectation.

[0081] It should be noted that when S3 / S2 is equal to 0, the area of S3 is 0, that is, when the installation hole 11 is not provided on the housing 10, the adjusting rod 90 is entirely located in the first chamber 81. Therefore, its adjusting function will fail, which is equivalent to Figures 1 to 3 the situation shown in the embodiment.

[0082] In a further embodiment, the ratio of S3 / S2 can be 0.6 ≤ S3 / S2 < 1. When S3 / S2 is within this range, the sizes of S3 and S2 are relatively close. In other words, the value of S3 is relatively large. Therefore, as Ph gradually decreases, the increasing amplitude of Pm decreases. In other words, the increase of Pm is relatively gentle, which is more suitable for offsetting the pressure loss in the medium-pressure pipeline (the first connecting pipe in the following text) when the medium-pressure pipeline is relatively long, so as to make the air pressure output to the air supply valve more stable.

[0083] It should be noted that there are various connection positions between the adjusting rod 90 and the sealing portion 30. For example, Figures 4 to 6In some embodiments shown, the axis of the adjusting rod 90 is coaxial with the piston rod 40. This arrangement ensures that the connection between the adjusting rod 90 and the sealing part 30 is on the axis of the piston rod 40, thus placing the forces between the adjusting rod 90, the sealing part 30, the piston rod 40, and the piston 20 on the same straight line. This avoids torque generation and improves the operating efficiency of the pressure reducer. However, this is not limiting. In other embodiments not shown, the adjusting rod 90 and the piston rod 40 can be parallel but not coaxial. For example, the adjusting rod 90 can also be connected to the pressure-bearing surface 31 of the sealing part 30, but it can be located off-center from the center of the pressure-bearing surface 31.

[0084] In other embodiments, the adjusting rod 90 may also be as follows: Figure 7 The L-shaped rod shown, the adjusting rod 90 can also be connected to the side wall of the sealing part 30, as long as it can achieve sealing and sliding relative to the housing 10 with the movement of the piston 20, and the connection position with the sealing part 30 does not affect the sealing of the flow hole 61 by the sealing part 30. In the embodiments of the present invention, no limitation is made.

[0085] And such Figure 7 As shown, when the adjusting rod 90 is an L-shaped rod and connected to the side wall of the sealing part 30, the adjusting rod 90 includes a longitudinal section 92 arranged along the first direction and a transverse section 91 connected between the longitudinal section 92 and the sealing part 30. One end of the longitudinal section 92 is located outside the housing 10, while the other end is connected to the transverse section 91. The transverse section 91 is subjected to the action of high-pressure gas in the first chamber 81 in its circumferential direction, and therefore is in a state of force balance. In the axial direction of the transverse section 91, the end connected to the longitudinal section 92 is balanced with the opposite side of the sealing part 30 in the circumferential direction. Therefore, the whole is in a state of balance. Since one end of the longitudinal section 92 of the adjusting rod 90 is located outside the first chamber 81 and is not affected by the high-pressure gas inside, the end of the longitudinal section 92 connected to the transverse section 91 will be affected by the high-pressure gas, generating a force Fx pointing towards the second end of the housing 10. Because the longitudinal section 92 is rigidly connected to the sealing part 30 through the transverse section 91, this Fx will be transmitted to the sealing part 30, thereby offsetting part of the effective force acting on the sealing part 30.

[0086] When the adjusting rod 90 is an L-shaped rod, regardless of the size of its transverse section 91, its longitudinal section 92 still needs to pass through the mounting hole 11. Therefore, it also needs to match the mounting hole 11.

[0087] For example, a sliding seal connection can be achieved between the adjusting rod 90 and the housing 10 by setting a sealing ring.

[0088] According to another aspect of the invention, such as Figure 8 and Figure 9 As shown, an air respirator is also disclosed, including the aforementioned mask 100, air source 200, pressure reducer 300, and alarm system 400. The air source 200 is connected to the first chamber 81 of the pressure reducer 300 to provide high-pressure gas. The alarm system 400 is connected to the second chamber 82 of the pressure reducer 300 and is triggered when the output pressure of the second chamber 82 reaches a preset threshold, thereby issuing an alarm. Furthermore, the alarm frequency of the alarm system 400 increases accordingly with the increase in output pressure. The pressure reducer 300 is connected to the alarm system 400 and receives gas that has been depressurized by the pressure reducer 300 for the user to breathe.

[0089] Specifically, a supply valve 600 and an exhaust valve 700 are installed on the mask 100. The supply valve 600 is connected between the air inlet of the mask 100 and the second chamber 82, and the exhaust valve 700 is connected to the exhaust port of the mask 100. High-pressure gas supplied by the air source 200 is reduced in pressure by the pressure reducer 300 before entering the supply valve 600. When the user inhales, the air pressure inside the mask 100 decreases, and the supply valve 600 opens, allowing medium-pressure gas from the second chamber 82 to flow through the supply valve 600 into the mask 100. The supply valve 600 further reduces the pressure of the medium-pressure gas from the second chamber 82 to a pressure suitable for human breathing, thus providing it to the user. When the user exhales, the air pressure inside the mask 100 increases, and the exhaust valve 700 opens, releasing the exhaled gas into the external environment.

[0090] The alarm system 400 can be a vibration alarm or an audible alarm. As one implementation method, such as... Figure 9 As shown, the vibration alarm includes a housing 401, a vibrating pin 402, a return spring 403, and an impact member 404. The impact member 404 is connected to the housing 401. The housing 401 contains a pneumatic cavity 405 and an air inlet channel 406. The air inlet end of the air inlet channel 406 communicates with a second chamber 82, and the air outlet end of the air inlet channel 406 communicates with an air inlet 407 of the pneumatic cavity 405. The pneumatic cavity 405 has an air outlet 408 communicating with the outside. The first end of the vibrating pin 402 is located inside the pneumatic cavity 405, and the second end is located outside the pneumatic cavity 405, for impacting the impact member 404. The spring is sleeved on the vibrating pin 402 and abuts against the inner wall of the pneumatic cavity 405, so that the first end of the vibrating pin 402 abuts against the air inlet 407 of the pneumatic cavity 405. For example, the impact member 404 can be made of a metal plate.

[0091] When the pressure Pm of the medium-pressure gas output from the second chamber 82 is less than a preset threshold, the first end of the vibrating pin 402 abuts against the air inlet 407, thereby blocking the air inlet 407. When the output pressure Pm of the second chamber 82 of the pressure reducer 300 reaches or exceeds the preset threshold, the force of the medium-pressure gas acting on the vibrating pin 402 overcomes the elastic force of the return spring 403, thereby pushing the vibrating pin 402 to move and disengage from the air inlet 407. At this time, the return spring 403 is compressed, and the second end of the vibrating pin 402 strikes the shock element 404. After the medium-pressure gas enters the pneumatic chamber 405 and is discharged from the air outlet 408, the air pressure in the pneumatic chamber 405 decreases, and the pressure acting on the first end of the vibrating pin 402 is less than the elastic force of the spring, thereby causing the vibrating pin 402 to block the air inlet 407 again. This process repeats, causing the vibrating pin 402 to move back and forth and strike the shock element 404, thereby generating a vibration signal that can be perceived by the user.

[0092] In some embodiments, the preset activation pressure threshold range of the alarm system 400 is 0.8 MPa to 0.9 MPa. That is, when the output pressure Pm of the second chamber 82 rises to the range of 0.8-0.9 MPa, the alarm system 400 is triggered. As Pm further increases, the piston oscillation frequency increases accordingly, and the frequency of the vibration signal increases accordingly.

[0093] It should be noted that in this embodiment, the alarm is a vibration alarm, but this is not limiting. As another implementation, the alarm system 400 can also use an auditory alarm with a whistle piston. When Pm reaches a preset threshold, the pressure causes the whistle piston to displace, thereby generating a whistling alarm sound, and the sound frequency increases with increasing Pm.

[0094] The face mask 100 is connected to the alarm system 400, and the alarm system 400 is connected to the pressure reducer 300 via air paths. These air paths can be constructed from flexible tubing, semi-flexible tubing, rigid tubing, metal tubing, or a combination of these components. For example, the face mask 100 is connected to one port of the alarm system 400 via a first air path, which can be constructed from a flexible tubing; the other port of the alarm system 400 is connected to the second chamber 82 of the pressure reducer 300 via a second air path, which can also be constructed from a flexible tubing.

[0095] When the output pressure Pm of the pressure reducer 300 continuously increases as the pressure Ph of the gas source 200 decreases, and reaches the preset activation threshold of the alarm system 400, the alarm system 400 is triggered and begins operation. As the pressure Ph of the gas source 200 further decreases, Pm continues to rise, and the alarm frequency of the alarm system 400 increases accordingly. By observing the trend of the alarm frequency, users can judge the decay of remaining gas volume in real time, thereby planning evacuation operations more scientifically.

[0096] For example, the range of S1 / S2 is 20≤S1 / S2≤100. Within this range, as Ph decreases, Pm changes significantly. Therefore, a more suitable linear boost characteristic with a suitable slope and linearity can be obtained, which is convenient for matching with alarm systems 400 of different specifications.

[0097] In the above embodiments, the application scenario of the air respirator can be the use of a portable air source 200 (e.g., an air cylinder). Therefore, the pipeline connecting the pressure reducer 300 and the air supply valve 600 is relatively short, usually within 2m. The pressure loss of the gas is small and negligible. Therefore, the degree of change of Pm can be appropriately increased so that it can reliably trigger the alarm system 400.

[0098] In some other embodiments, the pipeline connecting the pressure reducer 300 and the gas supply valve 600 may be relatively long, which can cause the gas pressure to drop as the gas passes through the pipeline, resulting in losses.

[0099] To solve this problem, in such Figure 10 Another embodiment shown also discloses an air respirator, which is basically the same as the above embodiment, except that in this embodiment, the user no longer carries the air source 200, which can be placed outside the work site. The air respirator also includes: a first connecting pipe 500, one end of which is connected to the second chamber 82 of the pressure reducer 300, and the other end is connected to the air supply valve 600. The length of the first connecting pipe is ≥10m, and the range of S1 / S2 is 20≤S1 / S2≤200.

[0100] Since the length of the first connecting pipe 500 is ≥10m, the pressure loss of the medium-pressure gas during transmission is relatively significant. However, after passing through the pressure reducer 300 in this embodiment, as the pressure of the high-pressure gas in the gas source 200 decreases from 30MPa to 2MPa, the output of the medium-pressure gas Pm gradually increases, and the output of Pm remains within a relatively comfortable range. This not only compensates for the pressure loss during transmission but also keeps the air pressure inside the mask 100 relatively stable, improving user comfort. Furthermore, the slope within this range means that fluctuations in Ph are significantly attenuated before being transmitted to Pm, and adjusting the ratio can yield different gains, facilitating matching with systems of different specifications.

[0101] For example, when adjusting the ratio of S3 to S2 using the adjusting rod 90, the range of S3 / S2 can be 0.6 ≤ S3 / S2 < 1. When S3 / S2 is within this range, the dimensions of S3 and S2 are relatively close, and the increase of Pm is relatively gradual. This is more suitable for offsetting the pressure loss in the first connecting pipe 500 when the first connecting pipe 500 is relatively long, thereby making the air pressure output to the air supply valve 600 more stable.

[0102] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A pressure reducer, characterized in that, include: The housing (10) has a first end and a second end along a first direction; A piston (20) is movably disposed within the housing (10) along a first direction, and the piston (20) is elastically connected to the first end of the housing (10); A partition structure is fixedly disposed inside the housing (10) and located between the piston (20) and the second end of the housing (10). A second chamber (82) is formed between the partition structure and the piston (20), and a first chamber (81) is formed between the partition structure and the second end of the housing (10). The partition structure is provided with a flow hole (61) connecting the first chamber (81) and the second chamber (82). The first chamber (81) is used to communicate with a gas source, and the second chamber (82) is used to output gas. A sealing part (30) is at least partially disposed in the first chamber (81) and connected to the piston (20). The position of the sealing part (30) corresponds to the flow hole (61). The sealing part (30) moves with the piston (20) to move relative to the flow hole (61), thereby opening or closing the flow hole (61). The portion of the sealing part (30) located in the first chamber (81) is provided with a pressure-bearing surface (31) to withstand pressure and transmit the force to the piston (20).

2. The pressure reducer according to claim 1, characterized in that, The partition structure is a partition plate (60) fixedly installed inside the housing (10), and the flow hole (61) is provided on the partition plate (60).

3. The pressure reducer according to claim 1, characterized in that, The sealing part (30) has a first end and a second end along the first direction. The first end of the sealing part (30) is connected to the piston (20), the second end of the sealing part (30) is away from the piston (20), and the end face of the second end of the sealing part (30) forms the pressure-bearing surface (31).

4. The pressure reducer according to claim 3, characterized in that, The sealing part (30) is a frustum or a sphere.

5. The pressure reducer according to claim 1, characterized in that, The pressure reducer also includes: An elastic element (50) is disposed between the piston (20) and the first end of the housing (10).

6. The pressure reducer according to claim 1, characterized in that, The piston (20) has a piston surface (21) facing the second chamber (82), the area of ​​the piston surface (21) is S1, the area of ​​the flow hole (61) is S2, and the range of S1 / S2 is 20≤S1 / S2≤200.

7. The pressure reducer according to claim 1, characterized in that, The flow passage (61) is a circular through hole.

8. The pressure reducer according to claim 1, characterized in that, When the blocking part (30) moves, it forms a flow channel with the flow hole (61), and the flow area of ​​the flow channel changes linearly with the movement of the blocking part (30).

9. The pressure reducer according to claim 8, characterized in that, The sealing part (30) is a frustum with a sloping side, and the sloping side forms the flow channel between the flow channel and the inner wall of the flow hole (61).

10. The pressure reducer according to claim 1, characterized in that, When the blocking part (30) moves, it forms a flow channel with the flow hole (61), and the flow area of ​​the flow channel changes non-linearly with the movement of the blocking part (30).

11. The pressure reducer according to claim 10, characterized in that, The sealing part (30) is a sphere, and its spherical surface forms the flow channel between the inner wall of the flow hole (61).

12. The pressure reducer according to claim 1, characterized in that, The pressure reducer also includes: An adjusting rod (90) is inserted through the housing (10) and slidably sealed to the housing (10). One end of the adjusting rod (90) is located inside the first chamber (81) and rigidly connected to the sealing part (30), while the other end is located outside the housing (10).

13. The pressure reducer according to claim 12, characterized in that, The housing (10) is provided with a mounting hole (11) communicating with the outside. The adjusting rod (90) passes through the mounting hole (11). The area of ​​the flow hole (61) is S2, the area of ​​the mounting hole (11) is S3, and the range of S3 / S2 is 0. <S3 / S2≤1。 14. The pressure reducer according to claim 13, characterized in that, The piston (20) has a piston surface (21) facing the second chamber (82), the area of ​​the piston surface (21) is S1, and the range of S1 / S2 is 20≤S1 / S2≤200.

15. An air respirator, characterized in that, The pressure reducer includes any one of claims 1 to 14.

16. The air respirator according to claim 15, characterized in that, The air respirator also includes: Face mask (100); A gas source (200) is connected to the first chamber (81) of the pressure reducer (300); An alarm system (400) is connected to the second chamber (82) of the pressure reducer (300) and is triggered when the output pressure of the second chamber (82) reaches a preset threshold. As the output pressure increases, the alarm frequency of the alarm system (400) increases accordingly.

17. The air respirator according to claim 16, characterized in that, The piston (20) has a piston surface (21) facing the second chamber (82), the area of ​​the piston surface (21) is S1, the area of ​​the flow hole (61) is S2, and the range of S1 / S2 is 20≤S1 / S2≤100.

18. The air respirator according to claim 15, characterized in that, The air respirator also includes: Face mask (100); Gas source (200); The first connecting pipe (500) has one end connected to the second chamber (82) of the pressure reducer (300) and the other end connected to the air supply valve (600).

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