Device for preventing air outlet chamber of respirator from freezing and closed circulation breathing system of engine

Abstract

The utility model discloses a device for preventing an air outlet chamber of a respirator from being frozen and an engine closed circulation breathing system, the device for preventing the air outlet chamber of the respirator from being frozen comprises a heating piece, the heating piece is provided with a heating cavity, the heating cavity is provided with an inlet and an outlet, and the inlet is communicated with a pressurized pipeline of a supercharger through a heating cavity air inlet pipe; the outlet is communicated with the respirator air outlet pipe through the heating cavity air outlet pipe. The temperature and pressure of gas acting through a gas compressor of the supercharger are high, the temperature of the gas is generally 60 DEG C or above, the high-temperature and high-pressure gas is supplied into the heating cavity through the heating cavity gas inlet pipe, heat is transmitted to the respirator gas outlet chamber through the heating cavity, and the risk that water is separated out when the gas entering the respirator gas outlet chamber is cooled is reduced; the air outlet chamber of the respirator is further prevented from freezing; and moreover, the temperature of the gas is inevitably increased after the gas compressor of the supercharger does work, so that the gas outlet chamber of the respirator can be effectively heated.

Description

Technical Field

[0001] The present application relates to the field of engine technology, and in particular to a device for preventing the icing of a respirator outlet chamber and an engine closed-circuit breathing system. Background Art

[0002] During normal engine operation, as the piston continues to reciprocate, a small amount of high-temperature and high-pressure gas will leak from the combustion chamber to the crankcase, causing the pressure in the crankcase to continue to increase. At the same time, as the engine works, the lubricating oil used for cooling will also carry some heat to the oil pan, causing the pressure in the crankcase to further increase.

[0003] The pressure in the engine's crankcase continues to rise, which can cause engine oil leakage and other faults. The crankcase releases pressure through a breather, which is a one-way valve.

[0004] In related technologies, such as Figure 1 As shown, the respirator outlet pipe 01 connects the compressor end of the supercharger 02 and the respirator outlet chamber 03. The exhaust gas discharged from the crankcase contains a large amount of water. When the engine is working in a cold area, the water in the exhaust gas will condense and freeze in the respirator outlet pipe 01 and the respirator outlet chamber 03, affecting the pressure release of the crankcase, causing faults such as oil spraying from the oil pan, and ultimately leading to serious faults such as cylinder scuffing.

[0005] In the related art, a heater is installed on the respirator outlet pipe 01, but no measures are provided in the respirator outlet chamber 03 to prevent condensation and icing. Therefore, large ice blocks are easily formed at the respirator outlet chamber 03, which hinders the respirator from exhausting air and causes the crankcase pressure to increase.

[0006] Therefore, how to solve the problem of condensation and ice formation in the air outlet chamber of the respirator has become a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0007] The present application proposes a device for preventing the respirator outlet chamber from freezing, so as to solve the problem of condensation and freezing in the respirator outlet chamber. The present application also proposes an engine closed-circuit breathing system.

[0008] In order to achieve the above-mentioned purpose, the present application provides a device for preventing ice from forming in a respirator outlet chamber, comprising a heating element arranged along the outer periphery of the respirator outlet chamber, the heating element having a heating chamber, the heating chamber having an inlet and an outlet, the inlet being connected to a post-compression pipeline of a supercharger through an air inlet pipe of the heating chamber, the outlet being connected to an air outlet pipe of the respirator through an air outlet pipe of the heating chamber, the heating element heating the respirator outlet chamber through the high-temperature gas generated by the post-compression pipeline.

[0009] Preferably, in the above device for preventing the ice formation in the breather outlet chamber, the inlet is arranged at one end of the heating chamber close to the cylinder head cover, and the outlet is arranged at one end of the heating chamber away from the cylinder head cover.

[0010] Preferably, in the above device for preventing the ice formation in the breather outlet chamber, a heat insulation layer is arranged on one side of the outer wall of the heating chamber away from the outer wall of the breather outlet chamber.

[0011] Preferably, in the above device for preventing the ice formation in the breather outlet chamber, the heating chamber is a cavity closed on all sides; or, the side of the heating chamber in contact with the breather outlet chamber is a cavity with an open end.

[0012] Preferably, in the above device for preventing the ice formation in the breather outlet chamber, the heating chamber is a spiral heating chamber.

[0013] Preferably, in the above device for preventing the ice formation in the breather outlet chamber, the outlet end of the air outlet pipe of the heating chamber is communicated with one end of the breather outlet pipe close to the supercharger.

[0014] An engine closed-loop respiratory system includes a breather outlet chamber, a breather outlet pipe and a supercharger. The breather outlet chamber is communicated with the compressor end of the supercharger through the breather outlet pipe, and further includes a device for preventing the ice formation in the breather outlet chamber.

[0015] The device for preventing the ice formation in the breather outlet chamber is the device for preventing the ice formation in the breather outlet chamber described in any one of the above solutions.

[0016] Preferably, in the above engine closed-loop respiratory system, the breather outlet pipe is communicated with the pre-compression pipeline of the supercharger.

[0017] Preferably, in the above engine closed-loop respiratory system, a heater is arranged on the breather outlet pipe.

[0018] Preferably, in the above engine closed-loop respiratory system, the heater is an electric heater.

[0019] The device for preventing the air outlet chamber of a respirator from icing provided by an embodiment of the present application includes a heating element disposed along the outer periphery of the air outlet chamber of the respirator. The heating element has a heating chamber with an inlet and an outlet. The inlet is communicated with the post-compression pipeline of a supercharger through a heating chamber inlet pipeline, and the outlet is communicated with the respirator outlet pipeline through a heating chamber outlet pipeline. The gas that has undergone the work of the compressor of the supercharger has relatively high temperature and pressure, and the gas temperature is generally above 60°C. The high-temperature and high-pressure gas is fed into the heating chamber through the heating chamber inlet pipeline, and the heat is transferred to the air outlet chamber of the respirator through the heating chamber, reducing the risk of water precipitation in the gas entering the air outlet chamber of the respirator due to cold, thereby preventing the air outlet chamber of the respirator from icing. This solution uses the high-temperature and high-pressure gas in the post-compression pipeline of the supercharger to heat the wall surface of the air outlet chamber of the respirator, without the need to introduce other heating devices. It will not only not excessively increase the cost of the device, but also the gas temperature will necessarily increase after undergoing the work of the compressor of the supercharger, which can effectively heat the air outlet chamber of the respirator and reduce the risk of icing of the air outlet chamber of the respirator. Moreover, the gas pressure will also increase after undergoing the work of the compressor of the supercharger, which can provide a self-driving force for the movement of the gas without the need to add other external power equipment.

[0020] The closed-loop respiratory system of an engine disclosed in this solution includes an air outlet chamber of a respirator, a respirator outlet pipeline, and a supercharger. The air outlet chamber of the respirator is communicated with the compressor end of the supercharger through the respirator outlet pipeline, and further includes a device for preventing the air outlet chamber of the respirator from icing. The device for preventing the air outlet chamber of the respirator from icing is the device for preventing the air outlet chamber of the respirator from icing described in any of the above solutions. Since the device for preventing the air outlet chamber of the respirator from icing has the above technical effects, the closed-loop respiratory system of the engine with this device for preventing the air outlet chamber of the respirator from icing also has the same technical effects, which will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings, and the present application can also be applied to other similar scenarios according to the provided drawings. Unless obvious from the language context or otherwise stated, the same reference numerals in the drawings represent the same structure or operation.

[0022] Figure 1 is a schematic structural diagram of a closed-loop respiratory system of an engine in the prior art;

[0023] Figure 2 is a schematic structural diagram of a closed-loop respiratory system of an engine of the present application;

[0024] Figure 3It is a schematic structural diagram of the device for preventing the ice formation in the air outlet chamber of the breathing apparatus and its connection with the post-compression pipeline and the air outlet chamber of the breathing apparatus.

[0025] The attached drawings are described as follows:

[0026] 01 - Breathing apparatus air outlet pipe; 02 - Supercharger; 03 - Breathing apparatus air outlet chamber;

[0027] 1 - Heating element; 2 - Heating chamber inlet pipe; 3 - Heating chamber outlet pipe; 4 - Post-compression pipeline; 5 - Breathing apparatus air outlet pipe; 6 - Breathing apparatus air outlet chamber; 7 - Cylinder head cover; 8 - Pre-compression pipeline; 9 - Heater. Detailed implementation manners

[0028] The present application will be further described in detail below with reference to the attached drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related application, rather than limiting the application. The described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without making creative efforts belong to the scope of protection of the present application.

[0029] It should be noted that for the sake of convenience of description, only the parts related to the relevant application are shown in the attached drawings. Without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other arbitrarily, as long as the combined technical features are not contradictory. All feasible feature combinations are the technical contents clearly recorded herein. Any one of the multiple sub-features included in the same statement can be applied independently, without necessarily being applied together with other sub-features.

[0030] As shown in the present application and the claims, unless the context clearly indicates an exceptional situation, words such as "a", "an", "one" and / or "the" are not specifically singular, but may also include plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, commodity or device including the element.

[0031] Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B; "and / or" herein is only a description of the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality" means two or more than two.

[0032] Please refer to Figures 1-3 .

[0033] Some embodiments of the present application disclose a device for preventing the ice formation in the air outlet chamber of a breather, including a heating element 1 disposed along the outer periphery of the air outlet chamber 6 of the breather for heating the air outlet chamber 6 of the breather to prevent the ice formation in the air outlet chamber 6 of the breather.

[0034] The heating element 1 has a heating chamber with an inlet and an outlet. The inlet is communicated with the post-compression pipeline 4 of the supercharger through the heating chamber inlet pipeline 2, and the outlet is communicated with the breather outlet pipeline 5 through the heating chamber outlet pipeline 3.

[0035] The gas that has done work by the compressor of the supercharger enters the post-compression pipeline 4 of the supercharger. The temperature and pressure of the gas in the post-compression pipeline 4 are relatively high. The gas temperature is generally above 60°C, and the temperature difference from the engine oil temperature in the oil pan is small. The engine oil temperature in the oil pan is between 80°C and 95°C. The high-temperature gas enters the heating chamber through the heating chamber inlet pipeline 2 and is transferred to the air outlet chamber 6 of the breather through the heating chamber, reducing the risk of water precipitation in the gas entering the air outlet chamber 6 due to cooling, and thus preventing the ice formation in the air outlet chamber 6 of the breather.

[0036] The device for preventing the ice formation in the air outlet chamber of the breather disclosed in this solution uses the high-temperature and high-pressure gas in the post-compression pipeline 4 of the supercharger to heat the wall surface of the air outlet chamber 6 of the breather. It does not need to introduce other heating devices, which will not excessively increase the cost of the device. Moreover, the temperature of the gas will necessarily increase after doing work by the compressor of the supercharger, which can effectively heat the air outlet chamber of the breather, reducing the risk of ice formation in the air outlet chamber 6 of the breather. In addition, the pressure of the gas will also increase after doing work by the compressor of the supercharger, which can provide a self-driving force for the movement of the gas and does not require additional external power equipment.

[0037] In addition, since the distance between the air outlet chamber 6 of the breather and the supercharger is relatively close, the settings of the heating chamber inlet pipeline 2 and the heating chamber outlet pipeline 3 are relatively simple and will not increase the layout difficulty of the device.

[0038] In the related art, only a heating structure is provided on the breather outlet pipeline 5, and there is no insulation or heating structure on the air outlet chamber 6 of the breather, making the air outlet chamber 6 of the breather a position with a relatively high risk of ice formation. This solution innovatively sets a heating element 1 on the air outlet chamber 6 of the breather, effectively reducing the risk of ice formation in the air outlet chamber 6 of the breather in cold regions.

[0039] Since ice formation is likely to occur at one end of the air outlet chamber 6 of the breather close to the cylinder head cover 7, the inlet of the heating chamber is set at one end of the heating chamber close to the cylinder head cover 7, and the outlet of the heating chamber is set at one end of the heating chamber far from the cylinder head cover 7, so that the relatively high-temperature gas acts on the position where ice formation initially occurs in the air outlet chamber 6 of the breather.

[0040] In the initial stage of icing in the air outlet chamber 6 of the respirator, small ice crystals can easily enter the compressor end of the supercharger through the air outlet pipe 5 of the respirator, damaging the impeller of the supercharger. In this solution, the inlet of the heating chamber is set at a position close to the air outlet chamber 6 of the respirator near the cylinder head cover 7, so that the gas with a higher temperature acts here, which can effectively prevent icing here, thereby reducing the risk of small ice crystals damaging the impeller of the compressor of the supercharger.

[0041] The shape of the heating chamber has various forms.

[0042] In some embodiments, such as Figure 2 and Figure 3 shown, the heating chamber is a spiral chamber, and the spiral chamber is spirally arranged along the outer wall of the air outlet chamber 6 of the respirator to heat each position in the axial and circumferential directions of the air outlet chamber 6 of the respirator.

[0043] In some other embodiments, the heating chamber is an annular chamber. The inner ring of the annular chamber has the same shape as the outer wall of the air outlet chamber 6 of the respirator, and the height of the annular chamber is at most equal to the height of the air outlet chamber 6 of the respirator to heat each position in the axial and circumferential directions of the air outlet chamber 6 of the respirator. In order to further optimize the above technical solution, a reverse flow structure can be arranged in the annular chamber to optimize the flow field of the gas in the annular chamber.

[0044] In the embodiment where the heating chamber is an annular chamber, the height of the annular chamber can be less than the height of the air outlet chamber 6 of the respirator. At this time, multiple annular chambers can be arranged in the height direction of the air outlet chamber 6 of the respirator.

[0045] In some other embodiments, the heating chamber can also be an arc chamber. The inner arc surface of the arc chamber fits the outer wall of the air outlet chamber 6 of the respirator. The height of the arc chamber is at most equal to the height of the air outlet chamber 6 of the respirator. The radian of the arc chamber can be 0° - 360°, excluding the end point values. Optionally, the radian of the arc chamber is 90°, 120°, 180°. At least two arc chambers are arranged in the circumferential direction of the air outlet chamber 6 of the respirator. Taking the radian of the arc chamber as 90° as an example, the number of arc chambers is at most 4.

[0046] In the embodiment where the heating chamber has multiple arc chambers, the radians of the multiple arc chambers can be equal or unequal.

[0047] In some other embodiments, the heating chamber can also be a coil structure arranged along the height direction of the air outlet chamber 6 of the respirator. Specifically, the coil structure reciprocally bends along the circumferential direction of the air outlet chamber 6 of the respirator in the height direction of the air outlet chamber 6 of the respirator.

[0048] In order to reduce the heat dissipation, a heat insulation layer is arranged on one side of the heating chamber away from the outer wall of the air outlet chamber 6 of the respirator, so that as much heat as possible of the heating chamber acts on the air outlet chamber 6 of the respirator.

[0049] The heat insulation layer can be arranged inside the heating cavity, or outside the heating cavity, or both inside and outside the heating cavity simultaneously.

[0050] The heating cavity can be a cavity structure with closed surroundings. In this case, the heating cavity is independent of the respirator outlet chamber 6, and the heat of the high-temperature and high-pressure gas in the heating cavity is transferred to the respirator outlet chamber 6 through the cavity wall of the heating cavity.

[0051] In this embodiment, the heating cavity and the respirator outlet chamber 6 can be made of the same material, or made of a material with high thermal conductivity.

[0052] The heating cavity can also be a cavity with an open end on the side that fits the respirator outlet chamber 6. The heating cavity is hermetically connected to the respirator outlet chamber 6 through the open end, and the heat of the high-temperature and high-pressure gas in the heating cavity is directly transferred to the respirator outlet chamber 6. In this embodiment, the open end of the heating cavity is sealed by the outer wall of the respirator outlet chamber 6, and the heating cavity and the respirator outlet chamber 6 form an integral structure.

[0053] In this embodiment, the heating cavity and the respirator outlet chamber 6 can be made of the same material, or made of a material with low thermal conductivity.

[0054] In the embodiment where the heating cavity is a spiral heating cavity, the cross-section of the spiral heating cavity can be semi-circular or strip-shaped, etc., to increase the contact area between the spiral heating cavity and the respirator outlet chamber 6 and improve the heat exchange efficiency between the heating cavity and the respirator outlet chamber 6.

[0055] In the embodiment where the heating cavity is a spiral heating cavity, the cross-sectional area of the spiral heating cavity is less than or equal to the cross-sectional area of the heating cavity inlet pipe 2 to increase the flow rate of the gas in the spiral heating cavity, thereby improving the heat exchange efficiency between the heating cavity and the respirator outlet chamber 6.

[0056] The high-temperature and high-pressure gas after heat exchange with the respirator outlet chamber 6 is discharged to the respirator outlet pipe 5 through the heating cavity outlet pipe 3, and then merged into the supercharger.

[0057] In some embodiments, the connection position of the heating cavity outlet pipe 3 and the respirator outlet pipe 5 is close to one end where the respirator outlet pipe 5 is connected to the supercharger, which extends the length of the heating cavity outlet pipe 3, makes the direction of the heating cavity outlet pipe 3 smoother, and reduces the pressure difference between the heating cavity outlet pipe 3 and the compressor end of the supercharger.

[0058] The intake pipe 2 of the heating chamber is connected to the post-compression pipeline 4 of the supercharger, and the outlet pipe 3 of the heating chamber is connected to the compressor end of the supercharger. The gas pressure in the intake pipe 2 of the heating chamber is higher than the gas pressure in the outlet pipe 3 of the heating chamber. This solution utilizes the pressure difference between the post-compression and pre-compression of the supercharger, as well as the advantage of the higher temperature of the post-compression gas, to ensure that the high-temperature gas heats the gas outlet chamber 6 of the respirator while ensuring that the gas can continuously and stably flow in the heating chamber of the heating element 1.

[0059] Optionally, the intake pipe 2 and the outlet pipe 3 of the heating chamber are flexible pipes and high-temperature resistant pipes to reduce the laying difficulty of the intake pipe 2 and the outlet pipe 3 of the heating chamber.

[0060] The intake pipe 2 and the outlet pipe 3 of the heating chamber are not limited to being made of flexible pipes, and can also be made of hard materials.

[0061] Optionally, the intake pipe 2 and the outlet pipe 3 of the heating chamber are made of the same material as the heating element 1, and heat insulation layers are provided on both the intake pipe and the outlet pipe to reduce the heat loss of the high-temperature and high-pressure gas when passing through the intake pipe and the outlet pipe.

[0062] This solution also discloses a closed-loop respiratory system for an engine, including a gas outlet chamber 6 of the respirator, an outlet pipe 5 of the respirator, and a supercharger. The gas outlet chamber 6 of the respirator is connected to the compressor end of the supercharger through the outlet pipe 5 of the respirator. As Figure 2 shown, the gas outlet chamber 6 of the respirator is arranged on the engine cylinder head cover 7.

[0063] The closed-loop respiratory system for an engine disclosed in this solution also includes a device for preventing the gas outlet chamber of the respirator from freezing, and the device for preventing the gas outlet chamber of the respirator from freezing is the device for preventing the gas outlet chamber of the respirator from freezing described in any of the above solutions.

[0064] Since the device for preventing the gas outlet chamber of the respirator from freezing has the above technical effects, the closed-loop respiratory system for an engine with this device for preventing the gas outlet chamber of the respirator from freezing also has the same technical effects, which will not be elaborated here.

[0065] In this solution, the connection position between the outlet pipe 5 of the respirator and the supercharger can be connected to the compressor end of the supercharger in the related art, or can also be connected to the pre-compression pipeline 8 of the supercharger.

[0066] The traditional breather outlet pipe 5 is connected to the compressor end of the supercharger. The breather outlet pipe 5 is closer to the blades of the compressor of the supercharger. In the condition where there are small ice particles in the breather outlet pipe 5, the small ice particles are more likely to be involved in the blades of the compressor of the supercharger, causing damage to the blades. By connecting the breather outlet pipe 5 to the pre-compressor pipeline 8 of the supercharger, making the breather outlet pipe 5 away from the blades of the compressor of the supercharger, the risk of ice particles formed in the breather outlet pipe damaging the blades of the compressor of the supercharger can be reduced. The breather outlet pipe 5 has a pre-heating chamber mixing pipeline and a post-heating chamber mixing pipeline. Among them, the pre-heating chamber mixing pipeline is the part of the breather outlet pipe 5 between the breather outlet chamber 6 and the heating chamber outlet pipe, and the post-heating chamber mixing pipeline is the part of the breather outlet pipe 5 between the heating chamber outlet pipe and the pre-compressor pipeline of the supercharger. In an extremely cold environment, ice particles are more likely to form in the pre-heating chamber mixing pipeline of the breather outlet pipe 5 than in the post-heating chamber mixing pipeline, and the ice particles will enter the post-heating chamber mixing pipeline under the action of the gas. In this solution, the connection position of the breather outlet pipe 5 to the supercharger is set on the pre-compressor pipeline 8, and the outlet of the breather outlet pipe 5 is away from the blades of the compressor of the supercharger, which can extend the ice melting time of the ice particles in the breather outlet pipe 5 and further reduce the risk of damage to the supercharger.

[0067] A heater 9 is provided on the breather outlet pipe 5. The heater 9 is used to heat the breather outlet pipe 5 to prevent icing inside the breather outlet pipe 5.

[0068] The closed-loop respiratory system of the engine disclosed in this solution not only has a device for preventing icing of the breather outlet chamber 6 on the breather outlet chamber 6, but also has a heater 9 on the breather outlet pipe 5. The two cooperate to effectively reduce the risk of icing of the breather, ensure that the breather can work stably and reliably, and ensure that the crankcase always operates within the set pressure range.

[0069] The heater 9 of the breather outlet pipe 5 can be an electric heater or a medium heat exchanger.

[0070] The heater 9 of the breather outlet pipe 5 is preferably arranged at one end of the breather outlet pipe 5 close to the supercharger to prevent small ice crystals from entering the supercharger and damaging the blades of the compressor of the supercharger.

[0071] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles, and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. The scope of the application involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above application concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present application.

Claims

1. A device for preventing the air outlet chamber of a respirator from freezing, characterized in that: The invention comprises a heating element (1) which is arranged along the outer periphery of a respirator air outlet chamber (6). The heating element (1) has a heating chamber, and the heating chamber has an inlet and an outlet. The inlet is connected to a post-compression pipeline (4) of a supercharger via a heating chamber air inlet pipe (2), and the outlet is connected to a respirator air outlet pipe (5) via a heating chamber air outlet pipe (3). The heating element (1) heats the respirator air outlet chamber (6) via high-temperature gas generated by the post-compression pipeline (4).

2. The device for preventing the respirator outlet chamber from freezing according to claim 1, characterized in that: The inlet is arranged at an end of the heating chamber close to the cylinder head cover (7), and the outlet is arranged at an end of the heating chamber away from the cylinder head cover (7).

3. The device for preventing the respirator outlet chamber from freezing according to claim 1, characterized in that: A heat-insulating layer is provided on one side of the outer wall of the heating chamber away from the air outlet chamber (6) of the respirator.

4. The device for preventing the respirator outlet chamber from freezing according to claim 1, characterized in that: The heating chamber is a cavity with four sides closed; or, the side of the heating chamber that is in contact with the air outlet chamber (6) of the respirator is a cavity with an open end.

5. The device for preventing the icing of the air outlet chamber of a respirator according to any one of claims 1 to 4, characterized in that: The heating chamber is a spiral heating chamber.

6. The device for preventing the icing of the air outlet chamber of a respirator according to any one of claims 1 to 4, characterized in that: The air outlet end of the heating chamber air outlet pipe (3) is in communication with an end of the respirator air outlet pipe (5) close to the supercharger.

7. An engine closed cycle breathing system, characterized in that: The invention comprises a respirator air outlet chamber (6), a respirator air outlet pipe (5) and a supercharger, wherein the respirator air outlet chamber (6) is connected to the compressor end of the supercharger through the respirator air outlet pipe (5), and also comprises a device for preventing the respirator air outlet chamber from freezing. The device for preventing the air outlet chamber of a respirator from freezing is the device for preventing the air outlet chamber of a respirator from freezing as described in any one of claims 1-6.

8. The engine closed cycle breathing system according to claim 7, characterized in that: The respirator air outlet pipe (5) is in communication with the pre-pressure pipeline (8) of the supercharger.

9. The engine closed cycle breathing system according to claim 7, characterized in that: A heater (9) is provided on the respirator air outlet pipe (5).

10. The engine closed cycle breathing system according to claim 9, characterized in that: The heater (9) is an electric heater.

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