A water-cooled oil-free scroll air compressor with direct connection between moving disc and stationary disc

Abstract

This invention relates to the field of air compressor technology, specifically to a direct-drive water-cooled oil-free scroll air compressor with a stationary and moving scroll plate. It includes an air compressor body, a scroll compression mechanism comprising a stationary scroll plate and a moving scroll plate, and an integrated cooling mechanism. The cooling mechanism includes an annular cooling structure located inside the moving scroll plate and a flow-around structure located inside the stationary scroll plate. This invention achieves circumferential oscillation and uniform heat dissipation by setting an annular concentric cavity coaxial with the root of the moving scroll teeth inside the moving scroll plate, pre-filling the concentric cavity with coolant, and rotating with the moving scroll plate base to achieve circumferential oscillation and uniform heat dissipation. Simultaneously, a double-layer circulating flow channel is set inside the stationary scroll plate, allowing the cooling medium to directly exchange heat with the stationary scroll teeth, forming a direct-drive water-cooled structure with closed-loop concentric ring cooling of the moving scroll plate and double-layer circulating cooling of the stationary scroll plate. This achieves direct heat dissipation of the core heat-generating areas of the moving and stationary scroll plates, shortens the heat transfer path, and improves the overall cooling efficiency of the machine.

Description

Technical Field

[0001] This invention relates to the field of air compressor technology, and more specifically, to a water-cooled oil-free scroll air compressor with direct connection between moving and stationary discs. Background Technology

[0002] An oil-free scroll air compressor is an energy-saving and environmentally friendly power device that compresses gas based on the principle of scroll meshing. Its core working components are a moving scroll and a stationary scroll. The moving scroll rotates within the stationary scroll, gradually reducing the volume of the closed compression chamber formed between them, thereby achieving staged compression of the gas. Finally, the compressed gas is discharged from the exhaust channel in the center of the stationary scroll. During continuous compression operation, the equipment generates a large amount of heat due to the work done in gas compression. If the heat continues to accumulate inside the machine, it can easily cause the overall temperature to rise, affecting the precision of the moving parts, compression efficiency, and the service life of the equipment. Therefore, efficient heat dissipation is required for the oil-free scroll air compressor.

[0003] For example, a water-cooled and heat-insulating oil-free scroll air compressor with Chinese patent publication number CN220791495U is provided. The air compressor is equipped with a drive, air compression, heat insulation and water cooling mechanism. The motor in the drive mechanism provides power through the main shaft. The air compression mechanism is composed of the air compressor housing and the internal moving and stationary discs. The heat insulation mechanism achieves heat insulation by using the heat insulation bearing and the air heat dissipation gap reserved between the mounting seat. The water cooling mechanism has a built-in spiral cooling channel from the center to the periphery and adopts the high and low arrangement of the inlet and outlet water ports to increase the cooling water capacity, thereby achieving dual protection of water cooling and heat insulation for the air compressor. However, during the compression process of an oil-free scroll air compressor, the meshing area between the moving and stationary discs is the main area where compression heat is generated and is also the hottest core part. Heat is indirectly dissipated through the shell, and the heat needs to be conducted to the cooling medium through multiple layers of the moving and stationary discs and the shell. The heat transfer path is long and the thermal resistance is high, resulting in relatively low overall cooling efficiency. This can easily cause thermal deformation of the moving and stationary discs due to high temperatures, which in turn affects the compression efficiency and operational stability of the air compressor. In view of this, there is an urgent need for a water-cooled oil-free scroll air compressor with direct connection between the moving and stationary discs to solve the above problems. Summary of the Invention

[0004] This invention provides a water-cooled oil-free scroll air compressor with direct-drive and stationary disc connection. It achieves direct-drive heat exchange and temperature field balance on both sides by setting a concentric cavity within the moving scroll disc and utilizing circumferential circulation of coolant for uniform heat dissipation. Simultaneously, it employs a double-layer flow channel within the stationary scroll disc to achieve heat dissipation and temperature field equilibrium on both sides. This allows for rapid heat dissipation from the core heating area of ​​the scroll compression mechanism, thereby solving the problems mentioned in the background art. During the operation of an oil-free scroll air compressor, heat is concentrated at the meshing point of the moving and stationary discs. Existing air compressors use indirect heat dissipation through the casing, which has a long path and low efficiency, and is prone to thermal deformation of the moving and stationary discs, thereby affecting the operating efficiency and stability of the air compressor.

[0005] To achieve the above objectives, the direct-drive water-cooled oil-free scroll air compressor includes an air compressor body, which consists of a main unit housing, a main unit end cover, a scroll compression mechanism, and a transmission mechanism. The scroll compression mechanism includes a stationary scroll and a moving scroll, which are meshed with each other inside the main unit housing. The transmission mechanism is connected to the moving scroll and drives the moving scroll to perform translational and revolutionary motion relative to the stationary scroll, thereby realizing the intake, compression, and discharge of gas. The vortex compression mechanism integrates a cooling mechanism, which includes an annular cooling structure disposed inside the moving vortex and a flow-around structure disposed inside the stationary vortex. The flow-around structure includes an annular flow channel. The annular cooling structure contains a cooling medium, and the relative motion of the cooling medium is driven by the translational and revolutionary motion of the moving scroll, so as to directly exchange heat with the moving scroll. The annular flow channel is connected to the external circulating cooling system. When the air compressor body is running, the cooling medium in the annular flow channel circulates and exchanges heat with the stationary volute. At the same time, it makes the temperature field on both sides of the stationary volute more uniform and suppresses pressure fluctuations during the compressed gas discharge process.

[0006] The above technical solution adopts a built-in direct-connection cooling structure for the moving and stationary discs, which can directly and efficiently dissipate heat from the core heat-generating parts. At the same time, it balances the temperature field on both sides of the stationary volute disc, effectively suppressing thermal deformation and exhaust pressure fluctuations, thereby ensuring the long-term efficient and stable operation of the air compressor.

[0007] Based on this, the annular cooling structure includes an annular concentric cavity opened inside the moving disk substrate, and the inner wall of the annular concentric cavity is provided with a liquid injection port, which is sealed after the cooling medium is injected. The annular concentric cavity is provided with multiple radial partitions, which are distributed at intervals along the circumference of the annular concentric cavity, dividing the annular concentric cavity into multiple sub-cavities arranged along the circumference. Multiple balancing holes are provided on each of the radial partitions, and the balancing holes connect adjacent sub-cavities to each other.

[0008] The annular concentric cavity can seal and contain the cooling medium, while the radial baffle and balance hole allow the cooling medium to circulate circumferentially with the translational revolution of the moving disk. This not only provides uniform heat dissipation to the moving disk, but also effectively reduces the vibration caused by coolant sloshing and improves the stability of the moving scroll.

[0009] In another technical solution, the annular flow channel includes a first flow channel layer and a second flow channel layer, which are connected by a straight cavity channel. The first flow channel layer is disposed in the stationary disk substrate near the stationary volute tooth, and it preferentially receives the cooling medium provided by the external circulating cooling system. When the cooling medium flows through the first flow channel layer, it directly absorbs the heat at the root of the stationary volute tooth. The straight cavity channel is located near the exhaust channel, guiding the cooling medium after heat exchange in the first flow channel layer to the second flow channel layer. The second flow channel layer is located in the stationary disk substrate at a position away from the stationary volute teeth, receiving the cooling medium from the straight cavity channel and exchanging heat on the back cavity side of the stationary disk substrate.

[0010] This technical solution achieves direct heat absorption at the root of the stationary volute by preferentially connecting the cooling medium to the high-temperature region corresponding to the first flow channel layer. Then, the cooled medium after heat exchange is guided to the second flow channel layer on the back cavity side of the stationary disk through the straight cavity channel, which performs secondary heat exchange on the back cavity side of the stationary disk substrate. This ensures efficient heat dissipation of the core heat-generating part of the stationary volute, balances the temperature field on both sides of the stationary disk substrate, reduces thermal deformation of the stationary disk due to temperature difference, and further stabilizes the gas temperature at the exhaust channel, suppresses exhaust pressure fluctuations, and improves the heat dissipation efficiency and operational stability of the stationary volute.

[0011] The first flow channel layer includes a central side and an outer side. The central side is the side closer to the exhaust channel, and the outer side is the side of the first flow channel layer away from the exhaust channel. The flow channel width of the central side is greater than the flow channel width of the outer side.

[0012] Multiple ribs are provided inside the flow channel on the central side. The multiple ribs are distributed at intervals along the extension direction of the first flow channel layer, and the multiple ribs and the inner wall of the first flow channel layer form a heat exchange flow channel.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In this direct-connection water-cooled oil-free scroll air compressor with moving and stationary discs, an annular concentric cavity coaxial with the root of the moving scroll tooth is set inside the moving scroll. The concentric cavity is pre-filled with coolant and rotates with the moving scroll base to achieve circumferential oscillation and uniform heat dissipation. At the same time, a double-layer circulation channel is set inside the stationary scroll, so that the cooling medium directly exchanges heat with the stationary scroll tooth. This forms a direct-connection water-cooling structure with closed concentric ring cooling of the moving scroll and double-layer circulation cooling of the stationary scroll. This achieves direct heat dissipation of the core heat-generating areas of the moving and stationary discs, shortens the heat transfer path, and improves the overall cooling efficiency of the machine. 2. In this direct-drive water-cooled oil-free scroll air compressor, by setting the stationary scroll tooth side with a higher temperature as the first flow channel layer for priority heat exchange, and using the cooled liquid after heat exchange to exchange heat with the second flow channel layer on the back cavity side with a lower temperature, the temperature field on both sides of the stationary scroll can be balanced, reducing pressure fluctuations caused by excessive temperature difference in the gas at the central exhaust channel, ensuring stable compressed gas discharge process, and improving the smooth operation of the air compressor. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the static vortex disk in the present invention; Figure 3 This is a schematic diagram of the structure in this invention where the moving scroll plate and the stationary scroll plate mesh to form a compression cavity; Figure 4 This is a structural diagram showing the location of the annular cooling structure in this invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the moving disk substrate in this invention; Figure 6 This is a schematic diagram of the annular flow channel in this invention; Figure 7 This is a cross-sectional view of the static disk substrate in this invention; Figure 8 This is a schematic diagram of the structure of the first flow channel layer in this invention; Figure 9 This is a schematic diagram of the structure of the second flow channel layer in this invention; Figure 10 This is a schematic diagram of the flow channel diameter of the first flow channel layer of the present invention.

[0015] The meanings of the labels in the diagram are as follows: 1. Air compressor body; 11. Main unit casing; 12. Main unit end cover; 13. Scroll compressor mechanism; 131. Stationary scroll; 132. Moving scroll; 14. Transmission mechanism; 21. Stationary disc base; 22. Stationary volute; 23. Moving disc base; 24. Moving volute; 25. Compression chamber; 26. Exhaust passage; 3. Cooling mechanism; 31. Circular cooling structure; 32. Flow-around structure; 311. Concentric cavity; 312. Radial diaphragm; 313. Balancing hole; 314. Sub-cavity; 320. Annular flow channel; 321. First flow channel layer; 322. Second flow channel layer; 323. Straight cavity channel; 324. Fin; 325. Heat exchange flow channel. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] In the existing technology, when the oil-free scroll air compressor is working, the meshing area of ​​the moving and stationary discs is the main heat-generating core and the temperature is relatively high. The existing heat dissipation mostly adopts the method of indirect water cooling of the shell. The heat needs to be conducted to the cooling medium through multiple layers of structure such as the moving and stationary discs and the shell. The heat transfer path is long and the thermal resistance is large. It is easy to cause thermal deformation of the moving and stationary discs due to high temperature, thereby reducing the compression efficiency of the air compressor. In view of this, the present invention provides a water-cooled oil-free scroll air compressor with direct connection between moving and stationary discs, see reference. Figures 1-6 As shown, the air compressor body 1 is composed of a main housing 11, a main end cover 12, a scroll compression mechanism 13, and a transmission mechanism 14. The scroll compression mechanism 13 includes a stationary scroll 131 and a moving scroll 132. The stationary scroll 131 and the moving scroll 132 are meshed with each other and disposed inside the main housing 11. The transmission mechanism 14 is connected to the moving scroll 132 and is used to drive the moving scroll 132 to perform translational and revolutionary motion relative to the stationary scroll 131 to realize the intake, compression and discharge of gas. The vortex compression mechanism 13 integrates a cooling mechanism 3. The cooling mechanism 3 is arranged to correspond to the heat generation areas of the moving vortex 132 and the stationary vortex 131 respectively. The cooling mechanism 3 includes an annular cooling structure 31 disposed inside the moving vortex 132 and a flow-around structure 32 disposed inside the stationary vortex 131. The flow-around structure 32 includes an annular flow channel 320. The annular cooling structure 31 contains the cooling medium and uses the translational and revolutionary motion of the moving scroll 132 to drive the cooling medium to generate relative motion, directly exchanging heat with the moving scroll 132, shortening the heat dissipation path of the moving scroll 132, and improving the heat dissipation uniformity of the moving scroll 132. The annular flow channel 320 is connected to the external circulating cooling system. When the air compressor body 1 is running, the cooling medium in the annular flow channel 320 circulates and exchanges heat with the stationary scroll 131.

[0018] See Figure 3 and combined Figure 4As shown, the stationary volute 131 is composed of a stationary volute base 21 and stationary volute teeth 22, and the moving volute 132 is composed of a moving volute base 23 and moving volute teeth 24. The helical directions of the stationary volute teeth 22 and the moving volute teeth 24 are matched. After the stationary volute teeth 22 and the moving volute teeth 24 are meshed and assembled, under the driving action of the transmission mechanism 14, the moving volute 132 will perform a translational revolution relative to the stationary volute 131. During this movement, the helical tooth surfaces of the stationary volute teeth 22 and the moving volute teeth 24 fit and cooperate with each other, thereby forming multiple closed crescent-shaped compression cavities 25 between them. As the moving volute 132 continues to perform translational revolution, these crescent-shaped compression cavities 25 will gradually move towards the central region of the stationary volute 131 along the extension direction of the helical tooth surface. At the same time, the volume of the compression cavity 25 will gradually shrink, thereby compressing the gas drawn into the cavity step by step, so that the pressure and temperature of the gas gradually increase.

[0019] Further integration Figure 2 and Figure 7 In the central region of the stationary vortex disk 131, an exhaust channel 26 is provided that penetrates the stationary disk base 21. The exhaust channel 26 is connected to the compression chamber 25. When the gas in the chamber is compressed to a preset pressure, it will be discharged from the center of the stationary vortex disk 131 through the exhaust channel 26, thus completing the complete operation process of gas compression and discharge.

[0020] In response to the heat exchange requirements of the 132 rotating scroll, combined with Figure 4 As shown, the annular cooling structure 31 includes an annular concentric cavity 311 opened inside the moving disk base 23. The inner wall of the annular concentric cavity 311 is machined with a liquid injection port (the liquid injection port preferably adopts a structure of threaded hole combined with sealing plug and fluororubber sealing gasket). After the cooling medium is injected, the sealing plug is tightened and the liquid injection port is sealed by the sealing gasket. Further integration Figure 5 The annular concentric cavity 311 is provided with multiple radial partitions 312. The radial partitions 312 are evenly distributed along the circumference of the annular concentric cavity 311, dividing the annular concentric cavity 311 into multiple circumferentially arranged sub-cavities 314. Each radial partition 312 is machined with a balance hole 313, which makes adjacent sub-cavities 314 connected.

[0021] Combining the translational and revolving motion characteristics of the moving volute 132, when the moving volute 132 performs translational and revolving motion, the annular concentric cavity 311 moves synchronously with the moving volute 132. Under the combined action of inertia and centrifugal force, the cooling medium in the concentric cavity 311 flows back and forth between adjacent sub-cavities 314 through the balance holes 313 on the radial partition 312. The flowing cooling medium continuously contacts the inner wall of the annular concentric cavity 311, directly absorbing the compressed heat conducted by the moving disk base 23 and the moving volute teeth 24, and then evenly dispersing the heat through its own flow, thus completing the direct heat exchange operation on the moving volute 132.

[0022] In combination with the overall setup of the aforementioned annular cooling structure 31, in order to achieve efficient and uniform heat exchange of the moving vortex 132 and adapt to the motion characteristics of the translational revolution of the moving vortex 132, the cooling medium in the annular concentric cavity 311 needs to be in a non-completely filled state, reserving a gas phase space to meet the flow and thermal expansion requirements of the cooling medium. First, the relationship between the fill factor and the total volume of the concentric cavity 311 and the fill volume of the cooling medium is clarified by the fill factor definition formula, combined with water-based coolant. Temperature rise of the 132-inch rotating scroll (Based on the actual operating conditions of the oil-free scroll air compressor, specifically the working temperature rise of the cooling medium, that is, the cooling medium rises from room temperature (20℃) to the stable temperature of the air compressor during operation (100℃), and the difference between the two is 80℃). The thermal expansion formula shows that the expansion of the cooling medium accounts for approximately 3.36% of the total cavity volume. To ensure sufficient flow and heat transfer of the cooling medium during the translational and orbital motion of the moving vortex disk, flow field simulation and kinematic analysis determine that the flow space volume accounts for 32% of the total cavity volume. Since the flow space itself is part of the gas phase space, and expansion compensation is also achieved in this space, the proportion of the gas phase space should not be less than the larger of the two, i.e., 32%, corresponding to a cooling medium filling degree not exceeding 68%. Considering both heat transfer effect and operational stability, and reserving a certain safety margin, the final cooling medium filling degree in the concentric cavity 311 can be set at 64%.

[0023] For the heat exchange arrangement corresponding to the stationary vortex disk 131, please refer to... Figure 6 and combined Figure 7 As shown, the annular flow channel 320 is divided into a first flow channel layer 321 and a second flow channel layer 322. The two flow channels are connected by a straight cavity channel 323 near the exhaust channel 26. The first flow channel layer 321 is arranged on the side of the stationary disk substrate 21 near the stationary volute 22. The cooling medium inlet of the annular flow channel 320 is located on one side of the first flow channel layer 321. The second flow channel layer 322 is arranged on the back cavity side of the stationary disk substrate 21 away from the stationary volute 22. The straight cavity channel 323 guides the cooling medium that has completed the heat exchange in the first flow channel layer 321 to the second flow channel layer 322. When the cooling medium flows through the first flow channel layer 321, it directly exchanges heat with the root region of the stationary volute 22. When it flows through the second flow channel layer 322, it exchanges heat with the back cavity side of the stationary disk substrate 21.

[0024] Based on the above-mentioned dual-layer flow channel structure, the low-temperature cooling medium provided by the external circulation cooling system preferentially enters the first flow channel layer 321 and directly absorbs the heat generated at the root of the stationary vortex 22 during gas compression by utilizing the temperature difference. After absorbing the heat, the cooling medium flows to the second flow channel layer 322 through the straight cavity channel 323. In the second flow channel layer 322, it continues to exchange heat with the back cavity side of the stationary disk substrate 21. Finally, the cooling medium carrying the heat flows out of the annular flow channel 320 and is cooled down by the external circulation cooling system, thereby forming a continuous circulating heat exchange process.

[0025] During the operation of the air compressor body 1, the core area of ​​gas compression is on one side of the stationary volute 22. The gas is compressed step by step inside the compression chamber 25. The heat generation in this area is relatively large, and the temperature level is higher than that of the back cavity side of the stationary disk base 21 away from the volute. Combining the gradient heat transfer principle, the first flow channel layer 321 is connected to the low-temperature cooling medium supplied by the external circulation system, which forms a high heat transfer intensity corresponding to the high temperature area of ​​the stationary volute 22. The second flow channel layer 322 uses the cooling medium after heat exchange in the first flow channel layer 321, which forms a suitable heat transfer intensity corresponding to the low temperature area of ​​the back cavity side of the stationary disk base 21. The heat transfer intensity on both sides is matched with the heat generation rate and temperature level of the corresponding area, so as to achieve the balance of the temperature field on both sides of the stationary volute 131.

[0026] Based on this temperature field equilibrium, the exhaust channel 26 at the center of the stationary vortex disk 131 forms a direct contact with the stationary disk substrate 21 with uniform temperature distribution. The heat transfer process between the compressed gas flowing through the exhaust channel 26 and the stationary disk substrate 21 remains stable during the discharge process. There will be no large local temperature differences between the gas and the surrounding structure, and the uniformity of temperature distribution inside the gas is improved. According to the relevant principles of the gas state equation, there is a corresponding correlation between the temperature change amplitude and the pressure change amplitude of the gas. When the gas temperature distribution tends to be stable, the pressure change amplitude in the exhaust channel 26 decreases accordingly, thereby suppressing the pressure fluctuation during the discharge process of the compressed gas.

[0027] Based on this double-layer flow channel heat exchange structure, combined with Figure 8 , Figure 9 and Figure 10 As shown, the first flow channel layer 321 is divided into a central side and an outer side according to its relative position to the exhaust channel 26. The central side is the region of the first flow channel layer 321 closest to the exhaust channel 26, and the outer side is the region of the first flow channel layer 321 furthest from the exhaust channel 26. The width of the flow channel on the central side of the first flow channel layer 321 is greater than the width of the flow channel on the outer side (e.g., ...). Figure 10In the diagram, dimension a represents the width of the outer flow channel of the first flow channel layer 321, and dimension b represents the width of the central flow channel of the first flow channel layer 321. Meanwhile, multiple ribs 324 are arranged inside the central flow channel of the first flow channel layer 321. The ribs 324 are distributed at intervals along the extension direction of the first flow channel layer 321. The ribs 324 cooperate with the inner wall of the first flow channel layer 321 to form a heat exchange channel 325 for the flow of cooling medium. Based on the structural configuration of the first flow channel layer 321, the larger flow channel width on the central side of the first flow channel layer 321 can increase the flow rate of the cooling medium in this area. The arrangement of the fins 324 can increase the contact area between the central side of the first flow channel layer 321 and the cooling medium. The heat exchange channel 325 can regulate the flow path of the cooling medium, making the flow state of the cooling medium in the heat exchange channel 325 more stable. The heat exchange area and heat exchange flux on the central side of the first flow channel layer 321 are improved. From the perspective of heat exchange matching principle, the center side of the first flow channel layer 321 is close to the exhaust channel 26. This area corresponds to the high temperature position at the end of gas compression, and the degree of heat accumulation is higher than that of the outer area. Setting the width of the flow channel on the center side to be greater than that on the outer side allows more cooling medium to enter this high temperature area, matching the amount of heat generated in the area. The fins 324 inside the flow channel can expand the heat exchange interface. When the cooling medium flows in the heat exchange flow channel 325 formed by the fins 324 and the inner wall of the flow channel, it can continuously contact the flow channel wall for heat exchange, directly absorbing the heat from the center side of the stationary vortex plate 131 and the area around the exhaust channel 26. Combined with the gradient heat exchange method of the double-layer flow channel, it further optimizes the heat exchange effect in the center area of ​​the stationary vortex plate 131.

[0028] The aforementioned external circulating cooling system, as is well known to those skilled in the art, mainly consists of a coolant storage tank, a circulating drive pump, a radiator, and supporting connecting pipes. The circulating drive pump provides power for the circulating flow of the coolant, and the radiator can dissipate the heat carried by the coolant to the external environment through air cooling or water cooling to maintain the coolant's low-temperature heat exchange state. The pipe connection method is as follows: the outlet end of the external circulating cooling system is connected to the cooling medium inlet of the annular flow channel 320 inside the stationary vortex plate 131 through a delivery pipe, and the cooling medium outlet end of the annular flow channel 320 is connected to the return end of the external circulating cooling system through a return pipe, thereby forming a complete closed-loop circulating cooling circuit to realize continuous circulating heat exchange of the coolant between the annular flow channel 320 and the external circulating cooling system.

[0029] It should be noted that, considering the operating conditions of the air compressor body 1 and the heat exchange requirements of the annular cooling structure 31 and the annular flow channel 320, deionized water can be selected as the cooling medium. Deionized water has a high thermal conductivity, good fluidity, is oil-free and pollution-free, and has good compatibility with the metal matrix of the annular concentric cavity 311 of the moving scroll 132 and the annular flow channel 320 of the stationary scroll 131. It can not only meet the heat exchange requirements of the reciprocating flow of the cooling medium in the annular cooling structure 31 as the moving scroll 132 moves and revolves, but also meet the continuous circulation heat exchange requirements of the external circulation cooling system. At the same time, it meets the basic requirements of oil-free air compressors for the cleanliness of compressed gas.

[0030] Furthermore, when the air compressor body 1 is in long-term operation, the cooling medium in the annular concentric cavity 311 flows back and forth under the action of inertia and centrifugal force, continuously absorbing heat from the moving plate base 23 and the moving volute 24. If the heat accumulation rate exceeds the heat dissipation rate of the cooling medium, the temperature of the cooling medium will continuously rise and gradually approach the temperature of the moving volute 132 base, and the heat exchange temperature difference between the two will be greatly reduced. In the prior art, when the air compressor body 1 is running continuously for a long time, routine inspections of the equipment are required. During the inspection, the operator can use an infrared thermometer to measure the temperature of the shell surface of the corresponding area of ​​the moving volute 132 outside the equipment. If the detected surface temperature is consistently higher than the normal operating temperature range of the model, it can be determined that the cooling medium inside the moving volute 132 is unable to exchange heat normally due to excessive temperature. To address this problem, when the air compressor body 1 is stopped, new deionized water can be replaced through the liquid injection port to restore the heat exchange capacity of the annular cooling structure 31 for the moving volute 132.

[0031] Working principle: When the air compressor body 1 is running, the transmission mechanism 14 drives the moving scroll 132 to perform translational revolution relative to the stationary scroll 131. The stationary scroll teeth 22 of the stationary scroll 131 and the moving scroll teeth 24 of the moving scroll 132 mesh with each other to form multiple crescent-shaped compression chambers 25. The compression chambers 25 move towards the center area of ​​the stationary scroll 131 with the translational revolution of the moving scroll 132 and their volume gradually decreases, completing the intake and step-by-step compression of gas. The compressed and heated gas is discharged through the exhaust channel 26 in the center of the stationary scroll 131, realizing the gas compression operation of the air compressor. At the same time, the cooling mechanism 3 integrated inside the vortex compression mechanism 13 carries out heat exchange work simultaneously. In the annular cooling structure 31 inside the moving vortex 132, the cooling medium moves with the moving vortex 132 in translation and revolution. Under the combined action of inertia and centrifugal force, it flows back and forth between the sub-cavities 314 of the annular concentric cavity 311 through the balance hole 313 of the radial partition 312. It directly absorbs the compression heat conducted by the moving disk base 23 and the moving vortex tooth 24 and distributes the heat evenly, thus completing the direct heat exchange of the moving vortex 132. The annular flow channel 320 inside the stationary vortex disk 131 forms a circulating heat exchange with the help of the external circulating cooling system. The low-temperature cooling medium preferentially enters the first flow channel layer 321 near the stationary vortex tooth 22, directly absorbing the compression heat at the root of the stationary vortex tooth 22, and then is guided to the second flow channel layer 322 on the back cavity side of the stationary disk substrate 21 through the straight cavity channel 323 for secondary heat exchange. Through the gradient heat exchange principle, the heat exchange intensity on both sides is matched with the temperature level of the corresponding area, so as to achieve the balance of the temperature field on both sides of the stationary vortex disk 131. The stationary disc substrate 21 with a uniform temperature field allows the compressed gas flowing through the exhaust channel 26 to transfer heat smoothly and have a uniform temperature distribution, reducing the variation range of gas state parameters and suppressing pressure fluctuations during the exhaust process. Finally, through the direct-connection water-cooled heat exchange structure of the moving and stationary discs, the heat dissipation requirements and operational stability of the core compression components of the air compressor are guaranteed.

[0032] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A water-cooled oil-free scroll air compressor with direct connection between moving and stationary discs, comprising an air compressor body (1), wherein the air compressor body (1) is composed of a main unit housing (11), a main unit end cover (12), a scroll compression mechanism (13), and a transmission mechanism (14), characterized in that: The vortex compression mechanism (13) includes a stationary vortex disk (131) and a moving vortex disk (132). The stationary vortex disk (131) and the moving vortex disk (132) are meshed with each other and disposed inside the main machine housing (11). The transmission mechanism (14) is connected to the moving vortex disk (132) for driving the moving vortex disk (132) to perform translational revolution relative to the stationary vortex disk (131) to realize the intake, compression and discharge of gas. The vortex compression mechanism (13) integrates a cooling mechanism (3), which includes an annular cooling structure (31) disposed inside the moving vortex (132) and a flow-around structure (32) disposed inside the stationary vortex (131). The flow-around structure (32) includes an annular flow channel (320). The annular cooling structure (31) contains a cooling medium inside and uses the translational revolution of the moving scroll (132) to drive the cooling medium to generate relative motion, thereby directly exchanging heat with the moving scroll (132). The annular flow channel (320) is connected to the external circulating cooling system. When the air compressor body (1) is running, the cooling medium in the annular flow channel (320) circulates and exchanges heat with the stationary volute (131). At the same time, it makes the temperature field on both sides of the stationary volute (131) equal and suppresses pressure fluctuations during the compressed gas discharge process.

2. The direct-drive water-cooled oil-free scroll air compressor according to claim 1, characterized in that: The stationary vortex disk (131) is composed of a stationary disk base (21) and stationary vortex teeth (22), and the moving vortex disk (132) is composed of a moving disk base (23) and moving vortex teeth (24). The stationary vortex teeth (22) and the moving vortex teeth (24) mesh with each other, forming multiple crescent-shaped compression cavities (25) between the stationary vortex disk (131) and the moving vortex disk (132). An exhaust channel (26) is provided in the central area of ​​the stationary vortex disk (131), and the exhaust channel (26) is connected to the compression cavity (25). The compressed gas is discharged from the center of the stationary vortex disk (131).

3. The direct-drive water-cooled oil-free scroll air compressor according to claim 2, characterized in that: The annular cooling structure (31) includes an annular concentric cavity (311) opened inside the moving disk base (23). The inner wall of the annular concentric cavity (311) is provided with a liquid injection port, which is sealed after the cooling medium is injected.

4. The direct-drive water-cooled oil-free scroll air compressor with moving and stationary discs according to claim 3, characterized in that: The cooling medium in the concentric cavity (311) is not fully filled, so as to reserve gas phase space in the annular concentric cavity (311).

5. The direct-drive water-cooled oil-free scroll air compressor according to claim 3, characterized in that: The annular concentric cavity (311) is provided with a plurality of radial partitions (312), which are distributed at intervals along the circumference of the annular concentric cavity (311) to divide the annular concentric cavity (311) into a plurality of circumferentially arranged sub-cavities (314).

6. The direct-drive water-cooled oil-free scroll air compressor according to claim 5, characterized in that: Multiple radial partitions (312) are provided with multiple balancing holes (313), which connect adjacent sub-cavities (314) to each other.

7. The direct-drive water-cooled oil-free scroll air compressor according to claim 2, characterized in that: The annular flow channel (320) includes a first flow channel layer (321) and a second flow channel layer (322). The first flow channel layer (321) and the second flow channel layer (322) are connected by a straight cavity channel (323). The first flow channel layer (321) is located in the stationary disk substrate (21) near the stationary volute (22). It preferentially receives the cooling medium provided by the external circulating cooling system. When the cooling medium flows through the first flow channel layer (321), it directly absorbs the heat at the root of the stationary volute (22).

8. The direct-drive water-cooled oil-free scroll air compressor according to claim 7, characterized in that: The straight cavity channel (323) is located near the exhaust channel (26) and guides the cooling medium after heat exchange in the first flow channel layer (321) to the second flow channel layer (322). The second flow channel layer (322) is located in the stationary disk substrate (21) away from the stationary volute (22) and receives the cooling medium from the straight cavity channel (323) to exchange heat on the back cavity side of the stationary disk substrate (21).

9. The direct-drive water-cooled oil-free scroll air compressor according to claim 7, characterized in that: The first flow channel layer (321) includes a central side and an outer side. The central side is the side close to the exhaust channel (26), and the outer side is the side of the first flow channel layer (321) away from the exhaust channel (26). The flow channel width of the central side is greater than the flow channel width of the outer side.

10. The direct-drive water-cooled oil-free scroll air compressor according to claim 9, characterized in that: Multiple ribs (324) are provided inside the flow channel on the center side. The multiple ribs (324) are distributed at intervals along the extension direction of the first flow channel layer (321). The multiple ribs (324) and the inner wall of the first flow channel layer (321) form a heat exchange flow channel (325).

Images