Volumetric variable displacement compressor

Abstract

The utility model discloses a positive displacement variable displacement compressor which comprises a compressor body, and an air pressure cavity is formed in the compressor body. The piston reciprocates along the length direction of the air pressure cavity; a piston ring which expands and / or resets according to the motion state of the piston is arranged on the peripheral surface of the piston; and the flow guide channel is arranged at the end part of the piston, and the flow direction of gas in the flow guide channel is adjusted according to the motion state of the piston. The piston ring is simple in structure, through the matching design of the flow guide channel and the piston ring, the piston ring is evenly stressed and expanded through air pressure changes in the downward movement process of the piston, so that the sealing performance between the piston ring and the cylinder body is enhanced, the working performance and efficiency of the compressor under different working conditions are effectively improved, the structure is simple and reliable, and the practicability is high. And a complicated control system is not needed, so that the manufacturing cost and the maintenance difficulty are reduced.

Description

Technical Field

[0001] This utility model relates to the field of compressor technology, specifically a positive displacement variable displacement compressor. Background Technology

[0002] Positive displacement compressors achieve gas intake, compression, and discharge through the reciprocating motion of a piston within a cylinder. Their core principle relies on the sealing performance between the piston and cylinder wall to maintain stable gas pressure. Under variable displacement conditions, the compressor needs to dynamically adjust its displacement according to external demand. In this case, the reliability of the piston-cylinder wall seal becomes a key factor affecting the compressor's efficiency and performance. However, traditional piston and piston ring structures have the following shortcomings:

[0003] First, conventional piston rings mostly employ rigid or semi-rigid designs, and their sealing performance primarily relies on initial preload and static friction. During variable operating conditions, the contact surface between the piston ring and cylinder wall is prone to increased sealing clearance due to wear, temperature fluctuations, or changes in axial pressure, leading to gas leakage, which in turn reduces volumetric efficiency and increases energy consumption. Second, existing variable displacement compressor sealing systems generally lack the dynamic response capability to pressure changes caused by piston movement. During the compression stroke, transient pressure fluctuations within the cylinder may exacerbate local stress concentration or airflow erosion at the sealing interface, leading to accelerated local wear of the piston ring. Meanwhile, the low-pressure environment during the intake stroke may cause backflow leakage due to insufficient sealing preload. This mismatch between the static sealing structure and the demands of dynamic operating conditions limits the potential for high-efficiency operation of variable displacement compressors across a wide operating range. Therefore, a positive displacement variable displacement compressor is proposed. Utility Model Content

[0004] The purpose of this invention is to provide a volumetric variable displacement compressor to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a positive displacement variable displacement compressor, comprising:

[0006] The compressor body, which contains a pressure chamber; and

[0007] A piston that reciprocates along the length of the pneumatic chamber; the outer circumferential surface of the piston is provided with piston rings that expand and / or return to their original position according to the piston's motion.

[0008] At least one flow channel is provided at the piston end, and the flow direction of the gas in the flow channel is adjusted according to the piston's motion state.

[0009] As a further embodiment of this utility model: the compressor body includes:

[0010] Cylinder block;

[0011] Front cover, which is fixed to one end of the cylinder block;

[0012] The rear cover is fixed to the other end of the cylinder block.

[0013] As a further aspect of this invention: a piston ring groove is formed on the outer surface of the piston, which is used to fix the piston ring.

[0014] As a further embodiment of this utility model: the inner wall of the piston ring is provided as an inwardly concave arc-shaped structure, and the concave arc surface is distributed along the circumference of the piston ring.

[0015] As a further aspect of this utility model: the ratio between the depth of the piston ring groove and the height of the piston ring is set between 0.5 and 1.0, and the initial radial interference of the piston ring in the piston ring groove is between 0 and 1.0 mm.

[0016] As a further embodiment of this utility model: the opening at one end of the flow channel is connected to the air pressure chamber, and the opening at the other end of the flow channel is connected to the piston ring groove.

[0017] As a further embodiment of this utility model: the number of the flow guiding channels is multiple, and the multiple flow guiding channels are arranged in a circular and uniform manner with the central axis of the piston as the reference.

[0018] As a further embodiment of this utility model, the flow guiding channel is specifically an irregularly shaped channel that gradually expands and / or shrinks.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] This application utilizes the design of the flow guide channel and piston rings to make the piston rings uniformly stressed and expand during the downward movement of the piston by taking advantage of the air pressure changes. This enhances the sealing performance between the piston rings and the cylinder, effectively improving the working performance and efficiency of the compressor under different operating conditions. The structure is simple and reliable, requiring no complex control system, thus reducing manufacturing costs and maintenance difficulty. Furthermore, it improves the sealing performance of the positive displacement compressor under different operating conditions, effectively reducing gas leakage, increasing the volumetric efficiency of the compressor, and reducing energy consumption. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the volumetric variable displacement compressor of this utility model;

[0022] Figure 2 This is a schematic diagram of the piston and piston ring assembly of this utility model;

[0023] Figure 3 This is a schematic diagram of the piston ring groove of this utility model;

[0024] Figure 4 This is a schematic diagram of the piston ring of this utility model;

[0025] Figure 5 This is a schematic diagram showing the direction of gas pressure flow when the piston of this utility model is in the compression stage;

[0026] Figure 6 This is a schematic diagram showing the piston ring of this utility model from its initial state to its expanded state;

[0027] In the diagram: 1. Cylinder block; 2. Piston; 3. Front cover; 4. Rear cover; 5. Air pressure chamber; 6. Piston ring groove; 7. Guide channel; 8. Piston ring. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figure 1-6 In this embodiment of the present invention, a volumetric variable displacement compressor includes:

[0030] The compressor body, which contains a pressure chamber 5; and

[0031] A piston 2 reciprocates along the length of the pneumatic chamber 5; the outer circumferential surface of the piston 2 is provided with a piston ring 8 that expands and / or resets according to the movement state of the piston 2.

[0032] At least one flow channel 7 is provided at the end of the piston 2, and the flow direction of the gas in the flow channel 7 is adjusted according to the movement state of the piston 2.

[0033] Specifically, the compressor body contains multiple pressure chambers 5, the number of which is the same as the number of pistons 2. Each pressure chamber 5 corresponds one-to-one with a piston 2, ensuring that each pressure chamber 5 is equipped with a piston 2, thereby achieving stable operation of the compressor. The presence of the pressure chambers 5 restricts the movement direction of the pistons 2. The number of guide channels 7 is not limited, and multiple guide channels 7 are evenly arranged in a circle on the end face of the pistons 2. This design ensures that the air pressure distribution entering the piston rings 8 is uniform, so that the piston rings 8 can be evenly stressed, avoiding local wear and uneven sealing, and extending the service life of the piston rings 8 and the pressure chambers 5. The piston 2 has two movement modes: compression and reset. In the compression stage, the piston 2 moves towards the end with the guide channel 7, which can compress the gas located in the pressure chamber 5, thereby increasing its pressure. In the reset stage, the piston 2 returns to its initial position, preparing for the next compression action. The state of the piston rings 8 and the guide channels 7 is adjusted accordingly based on the stage of the piston 2.

[0034] During operation, when piston 2 is in the compression stage, the volume of the pressure chamber 5 located on the side of the guide channel 7 decreases, and the air pressure increases. The increased air pressure enters the space between piston ring 8 and piston ring groove 6 through multiple evenly distributed guide channels 7, and acts evenly on the inner side of piston ring 8. At this time, under the action of air pressure, piston ring 8 overcomes its initial tension and expands radially outward, increasing the contact pressure between piston ring 8 and the inner wall of pressure chamber 5, thereby significantly improving sealing performance and effectively reducing gas leakage. When piston 2 is in the reset stage, the volume of the pressure chamber located on the side of the guide channel 7 increases, and the air pressure decreases. The air pressure returns to pressure chamber 5 through multiple evenly distributed guide channels 7. At this time, piston ring 8 returns to its initial state under the action of its own elastic restoring force, reducing the resistance to piston 2 movement and ensuring the efficient operation of the compressor.

[0035] The above technical solution utilizes the pressure changes generated during piston 2's movement to dynamically adjust the sealing performance of piston ring 8. By utilizing the pressure changes during piston 2's compression phase, piston ring 8 is uniformly expanded under force, enhancing the sealing performance with cylinder 1 and effectively improving the compressor's performance and efficiency under different operating conditions. When piston 2 is in the compression phase, piston ring 8 is in an expanded state, and when piston 2 is in the reset phase, piston ring 8 is in its initial state.

[0036] Please see Figure 1 In one embodiment, preferably, the compressor body includes:

[0037] Cylinder block 1;

[0038] Front cover 3, which is fixed to one end of cylinder body 1;

[0039] Rear cover 4, which is fixed to the other end of cylinder 1.

[0040] Specifically, the front cover 3 is fixed to one end of the cylinder block 1 with bolts, and the rear cover 4 is similarly fixed to the other end of the cylinder block 1 with bolts. The connection method between the cylinder block 1 and the front cover 3 and the rear cover 4 is as follows:

[0041] Please see Figure 2-4 In one embodiment, preferably, a piston ring groove 6 is formed on the outer surface of the piston 2. The piston ring groove 6 is used to fix the piston ring 8. The ratio between the depth of the piston ring groove 6 and the height of the piston ring 8 is set between 0.5 and 1.0, and the initial radial interference of the piston ring 8 in the piston ring groove 6 is between 0 and 1.0 mm. The inner wall of the piston ring 8 is set as an inwardly concave arc structure, and its concave arc surface is distributed along the circumference of the piston ring 8. The piston ring 8 is fixedly connected to the inner wall of the piston ring groove 6, and the piston ring 8 is made of a composite material with high elastic recovery ability and excellent wear resistance, such as carbon fiber reinforced rubber composite material, polyester fiber reinforced rubber composite material, etc. At this time, the piston ring 8 has an initial radial tension. In the natural state, the piston ring 8 maintains a certain gap with the inner wall of the air pressure chamber 5. When the piston 2 is in the compression stage, the piston ring 8 can expand radially outward uniformly under uniform pressure, tightly fit the cylinder wall, and achieve a good sealing effect.

[0042] Please see Figure 2-3 In one embodiment, preferably, the opening at one end of the flow channel 7 is connected to the air pressure chamber 5, and the opening at the other end of the flow channel 7 is connected to the piston ring groove 6. There are multiple flow channels 7, which are arranged in a circular and uniform manner with the central axis of the piston 2 as the reference. Specifically, the flow channel 7 is a gradually expanding and / or gradually contracting irregular channel to optimize the flow characteristics of gas in the flow channel 7 and ensure that the air pressure can be efficiently transmitted to the piston ring 8.

[0043] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0044] Therefore, the above description is only a preferred embodiment of this application and is not intended to limit the scope of this application; that is, all equivalent modifications made in accordance with the scope of the claims of this application shall be within the protection scope of the claims of this application.

Claims

1. A positive displacement variable displacement compressor, characterized in that, include: The compressor body has a pressure chamber formed inside it; A piston that reciprocates along the length of a pneumatic chamber, and the outer circumferential surface of the piston is provided with piston rings that expand and / or return to their original position according to the piston's motion. as well as At least one flow channel is provided at the piston end, and the flow direction of the gas in the flow channel is adjusted according to the piston's motion state.

2. The positive displacement variable displacement compressor according to claim 1, characterized in that, The compressor body includes: Cylinder block; Front cover, which is fixed to one end of the cylinder block; The rear cover is fixed to the other end of the cylinder block.

3. The positive displacement variable displacement compressor according to claim 1, characterized in that, The outer surface of the piston has a piston ring groove, which is used to fix the piston ring.

4. The positive displacement variable displacement compressor according to claim 3, characterized in that, The inner wall of the piston ring is designed as an inwardly concave arc-shaped structure, with the concave arc surface distributed along the circumference of the piston ring.

5. The positive displacement variable displacement compressor according to claim 4, characterized in that, The ratio between the depth of the piston ring groove and the height of the piston ring is set between 0.5 and 1.0, and the initial radial interference of the piston ring in the piston ring groove is between 0 and 1.0 mm.

6. The positive displacement variable displacement compressor according to claim 4, characterized in that, The opening at one end of the flow channel is connected to the air pressure chamber, and the opening at the other end of the flow channel is connected to the piston ring groove.

7. The positive displacement variable displacement compressor according to claim 1, characterized in that, The number of flow channels is multiple, and the multiple flow channels are evenly arranged in a circle with the central axis of the piston as the reference.

8. The positive displacement variable displacement compressor according to claim 7, characterized in that, The flow channel is an irregularly shaped channel that gradually expands and / or shrinks.

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