Air inlet pressure stabilizing and buffering mechanism and piston type air compressor

Abstract

The utility model provides an air inlet pressure stabilizing buffer mechanism and a piston type air compressor, the air inlet pressure stabilizing buffer mechanism comprises a crankcase and a buffer box, and the top wall of the crankcase is provided with a breathing hole; the buffer box is connected to the crankcase, an air inlet and an air outlet are formed in the buffer box, a bent airflow channel is formed between the air inlet and the air outlet in the buffer box, and the air outlet is used for being connected with an air inlet pipe of the compression cylinder; wherein a breathing cavity communicated with the breathing hole is formed in the buffer box, the breathing cavity is communicated with the airflow channel, an oil mist filter element is arranged in the breathing cavity, and the oil mist filter element is used for filtering oil mist mixed in air exhaled through the breathing hole. According to the air inlet pressure stabilizing and buffering mechanism and the piston type air compressor, the pulsation surge phenomenon of air inlet flow of the compression cylinder can be reduced, and the operation stability is improved; and the air pressure in the crankcase and the air pressure of the airflow channel can be kept balanced, so that the problem that the oil content of air in the crankcase is increased to influence the performance of a sealing element is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of air compressors, and in particular relates to an air intake pressure stabilizing buffer mechanism and a piston air compressor. Background Art

[0002] An air compressor is a device used to compress gas. The structure of an air compressor is similar to that of a water pump. Most air compressors are reciprocating piston type, rotary vane type or rotary screw type structures. Among them, a reciprocating piston air compressor uses a motor or other power source to drive the crankshaft assembly to rotate, thereby achieving reciprocating motion of the piston in the compression cylinder to perform work. Its advantage lies in its high pressure output range and gas compression efficiency. Therefore, most vehicle air compression systems use reciprocating piston air compressors to provide the necessary high-pressure air source to the braking system, suspension system and other auxiliary air devices.

[0003] Since the process of the crankshaft assembly rotating to drive the piston to reciprocate is a non-continuous air compression process, the reciprocating piston air compressor is prone to air flow pulsation and surge, which in turn leads to serious vibration and noise problems during the operation of the air compressor; in addition, the piston movement process will also cause the volume of the crankcase to change, thereby affecting the air pressure stability in the crankcase, which will cause the oil content of the air in the crankcase to increase, thereby affecting the performance and life of the seal. Utility Model Content

[0004] The utility model provides an air intake pressure stabilizing buffer mechanism and a piston air compressor, aiming to reduce air flow pulsation and surge during the operation of the piston air compressor and solve the problem that the oil content of the air in the crankcase increases and affects the performance of the seal.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: in the first aspect, an intake pressure stabilizing buffer mechanism is provided, including a crankcase and a buffer box, the top wall of the crankcase is provided with a breathing hole; the buffer box is connected to the crankcase, and an air inlet and an exhaust port are provided on the buffer box, and a curved air flow channel is formed between the air inlet and the exhaust port inside the buffer box, and the exhaust port is used to connect to the air intake pipe of the compression cylinder; wherein, a breathing chamber connected to the breathing hole is provided in the buffer box, the breathing chamber is connected to the air flow channel, and an oil mist filter is provided in the breathing chamber, and the oil mist filter is used to filter the oil mist mixed in the air exhaled through the breathing hole.

[0006] In combination with the first aspect, in a possible implementation, the buffer box is provided with a partition, which divides the inner cavity of the buffer box into an air inlet cavity and an exhaust cavity, and one end of the partition is provided with an air vent for connecting the air inlet cavity and the exhaust cavity; the air inlet is located at an end of the air inlet cavity away from the air vent, and the exhaust port is located at the cavity wall of the exhaust cavity and opposite to the partition, and the air inlet cavity, the air vent and the exhaust cavity together form a U-shaped airflow channel.

[0007] In some embodiments, a connecting plate is provided in the air intake cavity, which divides the air intake cavity into a first chamber and a second chamber, the first chamber is connected to the air inlet, the second chamber is connected to the air vent, and a center hole is provided on the connecting plate; wherein, an air intake filter is provided in the first chamber, an air intake duct is formed between the outer periphery of the air intake filter and the cavity wall of the first chamber, the air intake duct is connected to the air inlet, and the inner cavity of the air intake filter is aligned and connected to the center hole.

[0008] Exemplarily, one end of the air intake filter element away from the connecting plate is sealed with a mounting seat, the mounting seat is connected to the cavity wall of the first chamber away from the connecting plate and an air intake gap is provided therebetween; an expansion cavity is provided in the buffer box, the expansion cavity is located on the side of the air intake filter element away from the connecting plate and is connected to the air intake duct through the air intake gap, and the air inlet is provided at the bottom of the expansion cavity.

[0009] For example, an oil baffle is provided in the crankcase just below the breathing hole.

[0010] In a possible implementation, a through hole communicating with the air flow channel is provided at the top of the cavity wall of the breathing cavity, and an oil return hole communicating with the crankcase is provided at the bottom of the cavity of the breathing cavity.

[0011] In some embodiments, the inner cavity of the oil mist filter element is aligned and communicated with the breathing hole, an annular cavity is formed between the outer periphery of the oil mist filter element and the cavity wall of the breathing cavity, and the oil return hole is located at the bottom of the annular cavity.

[0012] Exemplarily, the oil return hole is connected to an oil return pipe, and the oil return pipe extends downward to the bottom of the crankcase.

[0013] For example, the buffer box is connected to an air filter, and the air filter is communicated with the air inlet.

[0014] The beneficial effect of the air intake pressure stabilizing buffer mechanism provided by the utility model is that: compared with the prior art, the air intake pressure stabilizing buffer mechanism of the utility model can utilize the curved air flow channel in the buffer box to buffer the air before it enters the compression cylinder, thereby reducing the pulsation and surging phenomenon of the air flow in the compression cylinder and improving the operating stability; at the same time, the crankcase is connected with the breathing chamber in the buffer box through the breathing hole. Since the breathing chamber is connected with the air flow channel, when the crankcase air pressure increases, it can be discharged into the breathing chamber and discharged into the air flow channel for utilization after being filtered by the oil mist filter element. When the air pressure in the crankcase drops, the air in the air flow channel can be replenished into the crankcase through the breathing chamber and the breathing hole, thereby making the air pressure in the crankcase always balanced with the air pressure in the air flow channel, thereby avoiding the problem of increased oil content in the air caused by changes in the air pressure in the crankcase, and avoiding the long-term infiltration of the seal in a large amount of oil mist to affect its sealing effect and service life.

[0015] In a second aspect, an embodiment of the utility model further provides a piston air compressor, comprising the above-mentioned intake pressure stabilizing and buffering mechanism.

[0016] Compared with the prior art, the piston air compressor provided by the utility model adopts the above-mentioned intake pressure stabilizing buffer mechanism, so that the curved air flow channel in the buffer box can be used to buffer the air before it enters the compression cylinder, thereby reducing the pulsation and surge phenomenon of the intake air flow in the compression cylinder and improving the operating stability; at the same time, the crankcase is connected with the breathing chamber in the buffer box through the breathing hole. Since the breathing chamber is connected with the air flow channel, when the crankcase air pressure increases, it can be discharged into the breathing chamber and discharged into the air flow channel for utilization after being filtered by the oil mist filter element. When the air pressure in the crankcase drops, the air in the air flow channel can be replenished into the crankcase through the breathing chamber and the breathing hole, thereby making the air pressure in the crankcase always balanced with the air pressure in the air flow channel, thereby avoiding the problem of increased oil content in the air caused by changes in the air pressure in the crankcase, and avoiding the sealing component from being infiltrated with a large amount of oil mist for a long time, which affects its sealing effect and service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the top view of the intake pressure stabilizing and buffering mechanism provided in an embodiment of the utility model;

[0018] Figure 2 For along Figure 1 Schematic diagram of the cross-sectional structure along the AA line;

[0019] Figure 3 For along Figure 1 Schematic diagram of the cross-sectional structure along the middle BB line;

[0020] Figure 4 for Figure 2 A schematic diagram of the local enlarged structure at C in the middle;

[0021] Figure 5 This is a schematic diagram of the internal structure of the buffer box used in the embodiment of the utility model.

[0022] In the figure: 10, crankcase; 11, breathing hole; 12, oil baffle; 13, oil lever; 20, buffer box; 201, air inlet; 202, exhaust port; 203, breathing chamber; 2031, perforation; 2032, oil return hole; 204, air inlet chamber; 2041, first chamber; 2042, second chamber; 205, exhaust chamber; 206, expansion chamber; 21, partition; 211, vent; 22, connecting plate; 221, center hole; 30, compression cylinder; 31, intake pipe; 40, oil mist filter element; 401, annular cavity; 50, intake filter element; 501, intake duct; 51, mounting seat; 60, oil return pipe; 70, air filter. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on another element or indirectly on another element. It should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "back", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" and "several" is two or more, unless otherwise clearly and specifically defined.

[0025] Please also read Figures 1 to 5 The air intake pressure stabilizing buffer mechanism provided by the utility model is now described. The air intake pressure stabilizing buffer mechanism comprises a crankcase 10 and a buffer box 20, the top wall of the crankcase 10 is provided with a breathing hole 11; the buffer box 20 is connected to the crankcase 10, and the buffer box 20 is provided with an air inlet 201 and an exhaust port 202, and a curved air flow channel is formed inside the buffer box 20 between the air inlet 201 and the exhaust port 202, and the exhaust port 202 is used to connect the air intake pipe 31 of the compression cylinder 30; wherein, a breathing chamber 203 connected to the breathing hole 11 is provided in the buffer box 20, the breathing chamber 203 is connected to the air flow channel, and an oil mist filter element 40 is provided in the breathing chamber 203, and the oil mist filter element 40 is used to filter the oil mist mixed in the air exhaled through the breathing hole 11.

[0026] It should be noted that the curved airflow channel arranged in the above-mentioned buffer box 20 can be serpentine, U-shaped or maze-shaped, and is intended to buffer the airflow pulsation by making the intake airflow change direction multiple times, so that the airflow reaches a stable state before entering the compression cylinder 30, which can not only alleviate the airflow surge phenomenon, but also help to reduce the airflow flow noise.

[0027] It should be understood that the volume of the crankcase 10 changes continuously during the reciprocating motion of the piston driven by the crankshaft assembly, which causes the air pressure in the crankcase 10 to rise and fall. The oil lever 13 on the crankshaft assembly brings up the lubricating oil at the bottom of the crankcase 10 to form a splash lubrication effect on the crankshaft assembly and the piston. When the air pressure in the crankcase 10 increases, it is more conducive to the mixing of the splashing oil mist with the air, which will cause the oil content in the air to increase. The seals in the crankcase 10, such as the connection seal between the crankshaft assembly and the crankcase 10, the seal between the piston and the compression cylinder 30, etc., are exposed to too much oil-containing air, which will cause the sealing performance to decrease, and also affect their service life.

[0028] Based on the above-mentioned causes of increased oil content in the air, in this embodiment, a breathing hole 11 is set on the top of the crankcase 10 to communicate with the breathing chamber 203 integrated in the buffer box 20, and on this basis, the breathing chamber 203 is connected to the air flow channel. That is to say, although there is no direct connection, the crankcase 10 and the air flow channel remain connected, so the air pressure in the crankcase 10 can maintain a balance with the air flow channel, that is, when the air pressure in the crankcase 10 increases, the oil-containing gas enters the breathing chamber 203 and is filtered by the oil mist filter element 40 and then discharged into the air flow channel. When the air pressure in the crankcase 10 decreases, gas is supplemented into the crankcase 10 through the air flow channel, thereby forming an air breathing process, thereby avoiding the problem of increased oil mist content in the air due to changes in the air pressure in the crankcase 10.

[0029] Compared with the prior art, the intake pressure stabilizing buffer mechanism provided in the present embodiment can utilize the curved airflow channel in the buffer box 20 to buffer the air before it enters the compression cylinder 30, thereby reducing the pulsation and surge phenomenon of the intake airflow of the compression cylinder 30 and improving the operating stability; at the same time, the crankcase 10 is connected with the breathing chamber 203 in the buffer box 20 through the breathing hole 11. Since the breathing chamber 203 is connected with the airflow channel, when the air pressure in the crankcase 10 increases, it can be discharged into the breathing chamber 203 and discharged into the airflow channel for utilization after being filtered by the oil mist filter element 40. When the air pressure in the crankcase 10 drops, the air in the airflow channel can be replenished into the crankcase 10 through the breathing chamber 203 and the breathing hole 11, thereby ensuring that the air pressure in the crankcase 10 is always balanced with the air pressure in the airflow channel, thereby avoiding the problem of increased oil content in the air caused by changes in the air pressure in the crankcase 10, and avoiding the sealing component from being infiltrated with a large amount of oil mist for a long time, thereby affecting its sealing effect and service life.

[0030] In some embodiments, see Figure 5The buffer box 20 is provided with a partition 21, which divides the inner cavity of the buffer box 20 into an air inlet cavity 204 and an air exhaust cavity 205, and one end of the partition 21 is provided with an air vent 211 for connecting the air inlet cavity 204 and the air exhaust cavity 205; the air inlet 201 is located at one end of the air inlet cavity 204 away from the air vent 211, and the air exhaust port 202 is located at the cavity wall of the exhaust cavity 205 and opposite to the partition 21, and the air inlet cavity 204, the air vent 211 and the exhaust cavity 205 together form a U-shaped airflow channel.

[0031] The interior of the buffer box 20 is divided into an intake chamber 204 and an exhaust chamber 205 by a partition 21, and the two are connected to each other through the vent hole 211 at the end of the partition 21, thereby forming a U-shaped airflow channel. This not only has a simple structure and low cost, but also enables the air to change direction at least twice before entering the compression cylinder 30, thereby playing a buffering and pressure-stabilizing role for the intake airflow, thereby reducing the surge phenomenon caused by airflow pulsation.

[0032] Furthermore, a connecting plate 22 is provided in the above-mentioned air intake cavity 204, and the connecting plate 22 divides the air intake cavity 204 into a first chamber 2041 and a second chamber 2042. The first chamber 2041 is connected to the air inlet 201, and the second chamber 2042 is connected to the air vent 211. A center hole 221 is provided on the connecting plate 22; wherein, an air intake filter element 50 is provided in the first chamber 2041, and an air intake duct 501 is formed between the outer periphery of the air intake filter element 50 and the cavity wall of the first chamber 2041, and the air intake duct 501 is connected to the air inlet 201, and the inner cavity of the air intake filter element 50 is aligned and connected to the center hole 221.

[0033] The main function of the connecting plate 22 is to fix the air intake filter element 50, and at the same time, to form an outside-in and inside-out filtering mode for the air intake filter element 50, so that the outside air enters the first chamber 2041 and then penetrates into the inner cavity of the air intake filter element 50 through the air intake duct 501. This process can not only filter the outside air, but also reduce the airflow pulsation, so that the airflow forms a relatively stable state after reaching the inside of the air intake filter element 50, and then enters the second chamber 2042 through the center hole 221 from the inner cavity of the air intake filter element 50, and then changes direction from the second chamber 2042 and enters the exhaust chamber 205 through the air vent 211, and finally enters the exhaust port 202 from the exhaust chamber 205 and flows to the compression cylinder 30. During the whole process, the airflow undergoes several changes of direction, which is beneficial to enhance the pressure stabilizing and buffering effect of the buffer box 20 on the intake airflow of the compression cylinder 30, and reduce the airflow pulsation and surge.

[0034] It should be noted that see Figure 5One end of the air intake filter 50 away from the connecting plate 22 is blocked with a mounting seat 51, and the mounting seat 51 is connected to the cavity wall of the first chamber 2041 away from the connecting plate 22 and there is an air intake gap between the two; an expansion cavity 206 is provided in the buffer box 20, and the expansion cavity 206 is located on the side of the air intake filter 50 away from the connecting plate 22 and is connected to the air intake duct 501 through the air intake gap, and the air inlet 201 is arranged at the cavity bottom of the expansion cavity 206.

[0035] The outside air first enters the expansion chamber 206 from bottom to top, and then turns into horizontal flow in the expansion chamber 206. When the airflow reaches the position of the mounting seat 51, it is blocked by the mounting seat 51 and changes direction to diffuse into the air intake gap at the edge of the mounting seat 51, and then can enter the air intake duct 501. This process again increases the number of airflow changes, thereby improving the pulsation buffering effect of the intake airflow and reducing airflow surge and noise.

[0036] In some embodiments, Figure 4 As shown, an oil baffle plate 12 is provided in the crankcase 10 just below the breathing hole 11. The oil baffle plate 12 can block the oil droplets and oil mist splashing toward the breathing hole 11, thereby reducing the amount of oil mist entering the breathing cavity 203 along with the air, thereby preventing the amount of oil mist entering the oil mist filter element 40 from being too large and affecting the oil filtering effect of the oil mist filter element 40, and also helping to extend the service life of the oil mist filter element 40.

[0037] For some possible implementations, see Figure 4 The top of the cavity wall of the breathing cavity 203 is provided with a perforation 2031 connected to the air flow channel, and the bottom of the breathing cavity 203 is provided with an oil return hole 2032 connected to the crankcase 10. Since the oil mist filter 40 collects the oil mist in the air at the bottom of the breathing cavity 203 after filtering it, the oil return hole 2032 is provided at the bottom of the breathing cavity 203 to return the collected oil to the crankcase 10, thereby avoiding oil waste. At the same time, the perforation 2031 is provided at the top of the breathing cavity 203. On the one hand, it can prevent the breathing cavity 203 from bringing out oil mist and polluting the air quality in the air flow channel when exhaling into the air flow channel. On the other hand, when the breathing cavity 203 inhales from the air flow channel, the oil collected at the bottom can be quickly blown into the oil return hole 2032 by the flow of air from top to bottom, thereby avoiding the oil staying at the bottom of the breathing cavity 203 for a long time and improving the oil return efficiency.

[0038] Specifically, the inner cavity of the oil mist filter 40 is aligned and connected with the breathing hole 11, and an annular cavity 401 is formed between the outer periphery of the oil mist filter 40 and the cavity wall of the breathing cavity 203, and the oil return hole 2032 is located at the bottom of the annular cavity 401. When the crankcase 10 exhales outward, the oil-containing air flows outward from the inner cavity of the oil mist filter 40, thereby blocking most of the oil mist inside the oil mist filter 40 and returning to the crankcase 10 through the breathing hole 11 along with the inhalation process of the crankcase 10. At the same time, part of the oil mist penetrates the outer surface of the oil mist filter 40 to form oil droplets and flows downward to the bottom of the annular cavity 401. At this time, this part of the oil can be returned to the crankcase 10 through the oil return hole 2032, thereby avoiding excessive oil accumulation in the annular cavity 401 and affecting the cleanliness of the air entering the air flow channel.

[0039] In order to prevent the oil from dripping from the oil return hole 2032 into the crankcase 10 and contacting the high-pressure air again to form oil mist and enter the breathing chamber 203, as shown in FIG. Figure 3 and Figure 4 As shown, the oil return hole 2032 is connected to an oil return pipe 60, which extends downward to the bottom of the crankcase 10. The oil return pipe 60 is used to guide the dripping oil to the bottom of the crankcase 10, thereby preventing the return oil from directly contacting the high-pressure air and causing an increase in the oil mist content in the air.

[0040] It should be noted that if Figure 3 and Figure 5 As shown, the buffer box 20 is connected with an air filter 70, and the air filter 70 is connected with the air inlet 201. The air filter 70 can improve the cleanliness of the air entering the buffer box 20, and prevent impurities from entering the compression cylinder 30 and affecting normal operation. At the same time, the air filter 70 also has a certain air intake buffering effect, which is conducive to reducing air intake pulsation.

[0041] Based on the same inventive concept, Figures 1 to 5 It is understood that an embodiment of the present application also provides a piston air compressor, including the above-mentioned intake pressure stabilizing and buffering mechanism.

[0042] Compared with the prior art, the piston air compressor provided in this embodiment adopts the above-mentioned intake pressure stabilizing buffer mechanism, so that the curved air flow channel in the buffer box 20 can be used to buffer the air before it enters the compression cylinder 30, thereby reducing the pulsation and surge phenomenon of the intake air flow in the compression cylinder 30 and improving the operating stability; at the same time, the crankcase 10 is connected with the breathing chamber 203 in the buffer box 20 through the breathing hole 11. Since the breathing chamber 203 is connected with the air flow channel, when the air pressure in the crankcase 10 increases, it can be discharged into the breathing chamber 203 and filtered by the oil mist filter element 40 and then discharged into the air flow channel for use. When the air pressure in the crankcase 10 drops, the air in the air flow channel can be replenished into the crankcase 10 through the breathing chamber 203 and the breathing hole 11, thereby ensuring that the air pressure in the crankcase 10 is always balanced with the air pressure in the air flow channel, thereby avoiding the problem of increased oil content in the air caused by changes in the air pressure in the crankcase 10, and avoiding the seal from being infiltrated with a large amount of oil mist for a long time, which affects its sealing effect and service life.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. The air intake pressure stabilizing and buffering mechanism is characterized in that: include: The crankcase has a breathing hole on the top wall; A buffer box connected to the crankcase, the buffer box is provided with an air inlet and an exhaust port, a curved air flow channel is formed inside the buffer box between the air inlet and the exhaust port, and the exhaust port is used to connect to the air inlet pipe of the compression cylinder; Wherein, a breathing cavity connected to the breathing hole is provided in the buffer box, the breathing cavity is connected to the airflow channel, and an oil mist filter is provided in the breathing cavity, and the oil mist filter is used to filter the oil mist mixed in the air exhaled through the breathing hole.

2. The intake pressure stabilizing and buffering mechanism according to claim 1, characterized in that: The buffer box is provided with a partition, which divides the inner cavity of the buffer box into an air inlet cavity and an exhaust cavity, and one end of the partition is provided with an air vent for connecting the air inlet cavity and the exhaust cavity; the air inlet is located at one end of the air inlet cavity away from the air vent, and the exhaust is located at the cavity wall of the exhaust cavity and opposite to the partition, and the air inlet cavity, the air vent and the exhaust cavity together form a U-shaped airflow channel.

3. The air intake pressure stabilizing and buffering mechanism according to claim 2, characterized in that: A connecting plate is provided in the air intake cavity, and the connecting plate divides the air intake cavity into a first chamber and a second chamber, the first chamber is connected to the air inlet, and the second chamber is connected to the air vent, and a center hole is provided on the connecting plate; wherein, an air intake filter is provided in the first chamber, and an air intake duct is formed between the outer periphery of the air intake filter and the cavity wall of the first chamber, the air intake duct is connected to the air inlet, and the inner cavity of the air intake filter is aligned and connected to the center hole.

4. The intake pressure stabilizing and buffering mechanism according to claim 3, characterized in that: One end of the air intake filter element away from the connecting plate is blocked with a mounting seat, and the mounting seat is connected to the cavity wall of the first chamber away from the connecting plate and an air intake gap is provided therebetween; an expansion cavity is provided in the buffer box, and the expansion cavity is located on a side of the air intake filter element away from the connecting plate and is connected to the air intake duct through the air intake gap, and the air inlet is provided at the cavity bottom of the expansion cavity.

5. The intake pressure stabilizing and buffering mechanism according to claim 1, characterized in that: An oil baffle is provided in the crankcase just below the breathing hole.

6. The intake pressure stabilizing and buffering mechanism according to claim 1, characterized in that: A through hole communicating with the air flow channel is provided at the top of the cavity wall of the breathing cavity, and an oil return hole communicating with the crankcase is provided at the bottom of the cavity of the breathing cavity.

7. The intake pressure stabilizing and buffering mechanism according to claim 6, characterized in that: The inner cavity of the oil mist filter is aligned and communicated with the breathing hole, an annular cavity is formed between the outer periphery of the oil mist filter and the cavity wall of the breathing cavity, and the oil return hole is located at the bottom of the annular cavity.

8. The intake pressure stabilizing and buffering mechanism according to claim 6, characterized in that: The oil return hole is connected with an oil return pipe, and the oil return pipe extends downward to the bottom of the crankcase.

9. The air intake pressure stabilizing and buffering mechanism according to any one of claims 1 to 8, characterized in that: The buffer box is connected with an air filter, and the air filter is communicated with the air inlet.

10. A piston air compressor, characterized in that: It comprises an intake pressure stabilizing and buffering mechanism as described in any one of claims 1 to 9.

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