Oil-free vortex air compressor

Abstract

The oil-free scroll air compressor comprises a movable scroll plate and a static scroll plate, the movable scroll plate can eccentrically rotate around the center of the static scroll plate, the movable scroll plate and the static scroll plate are each provided with a protective layer, the thickness of each protective layer is D, the profile tolerance of movable scroll teeth is a1, and the profile tolerance of static scroll teeth is a2, a preset gap between meshing points of the movable scroll wrap and the static scroll wrap is b, the minimum effective thickness of the protective layer is c, and D = a1 + a2 + b + c. According to the scroll compressor, the profile tolerance of the movable scroll plate and the static scroll plate and the actual eccentricity influence of the movable scroll plate are fully considered, and when the movable scroll teeth are influenced by the actual center change amount and the profile tolerance of the movable scroll teeth and the static scroll teeth in the eccentric movement process of the movable scroll plate, the movable scroll teeth are excessively close to the static scroll teeth; the protective layer still has sufficient thickness allowance so as to ensure that the protective layer is not damaged or invalid due to abrasion caused by excessive approaching of the movable scroll wrap and the static scroll wrap.

Description

Technical Field

[0001] The present application belongs to the technical field of scroll compressors, and in particular relates to an oil-free scroll air compressor. Background Art

[0002] As a gas compression device, oil-free scroll air compressor has the characteristics of compact structure, low noise and smooth operation, and is particularly suitable for application scenarios that require low noise and stable airflow. Especially in the medical industry, since oil-free scroll air compressors can provide high-quality compressed air, they are widely used in equipment such as oxygen generators that have high requirements for air compression efficiency and noise control.

[0003] The working principle of the oil-free scroll air compressor is to use two scrolls to mesh with each other to compress the gas. The motor drives the movable scroll to rotate around the fixed scroll to form a gradually decreasing air cavity. The movable scroll and the fixed scroll are the most important friction parts in the scroll air compressor. The meshing accuracy of the two directly determines the sealing of the compression chamber, and then determines the air compression efficiency. However, due to the influence of processing accuracy, there is a deviation between the actual eccentricity and the theoretical eccentricity of the movable scroll when it performs eccentric motion. In addition, when the movable scroll performs eccentric motion, the friction between the compressed air and the fixed scroll will generate high heat, causing the movable scroll and the fixed scroll to expand and deform. The superposition of these factors can easily lead to wear between the movable scroll and the fixed scroll. In the prior art, a protective layer is usually provided on the orbiting scroll and the stationary scroll to reduce the direct contact between the orbiting scroll and the stationary scroll. However, if the protective layer is too thin, it may be worn out due to the mutual friction between the orbiting scroll and the stationary scroll, resulting in failure of protection and affecting the protection effect. If the protective layer is too thick, it may affect the thickness uniformity of the protective layer, increase the roughness of the protective layer, and affect the sealing effect and manufacturing cost. Summary of the invention

[0004] The present application provides an oil-free scroll air compressor to solve the technical problems of easy wear of the movable scroll and the stationary scroll and poor compression effect in the traditional oil-free scroll air compressor.

[0005] The technical solution adopted in this application is:

[0006] An oil-free scroll air compressor comprises a movable scroll and a stationary scroll, wherein the movable scroll comprises a movable scroll body and a movable scroll tooth, and the stationary scroll comprises a stationary scroll body and a stationary scroll tooth. The movable scroll can rotate eccentrically around the center of the stationary scroll so that the movable scroll tooth performs meshing motion relative to the stationary scroll tooth. The movable scroll and the stationary scroll are respectively provided with a protective layer, the thickness of the protective layer is D, the contour of the movable scroll tooth is a1, the contour of the stationary scroll tooth is a2, the preset gap between the meshing point of the movable scroll tooth and the stationary scroll tooth is b, and the minimum effective thickness of the protective layer is c, D=a1+a2+b+c; wherein the service life of the oil-free scroll air compressor is not less than 12000h, and the outlet pressure is not less than 3bar.

[0007] The oil-free scroll air compressor described in this application also includes the following additional technical features:

[0008] The movable scroll and the fixed scroll are both made of aluminum alloy material, and the protective layer is constructed of a hard oxide film formed by oxidation of the movable scroll and the fixed scroll.

[0009] The contour a1 of the movable scroll satisfies 5μm≤a1≤20μm, the contour a2 of the stationary scroll satisfies 5μm≤a2≤20μm, the minimum effective thickness c of the protective layer satisfies 5μm≤c≤10μm, and the distance of the preset gap b satisfies 5μm≤b≤20μm.

[0010] A first anti-wear gap is provided between the top of the movable scroll gear and the stationary plate body, and a second anti-wear gap is provided between the top of the stationary scroll gear and the movable plate body.

[0011] A first receiving groove is provided at the top of the movable scroll gear, a first sealing strip is provided in the first receiving groove, and the first sealing strip abuts against the static disk body; a second receiving groove is provided at the top of the static scroll gear, a second sealing strip is provided in the second receiving groove, and the second sealing strip abuts against the movable disk body.

[0012] Along the extension direction of the first accommodating groove, a plurality of first air accommodating grooves are provided at intervals on both sides of the first accommodating groove at the top of the movable scroll tooth; along the extension direction of the second accommodating groove, a plurality of second air accommodating grooves are provided at intervals on both sides of the second accommodating groove at the top of the fixed scroll tooth.

[0013] The first sealing strip is made of modified PTFE material, and / or the second sealing strip is made of modified PTFE material.

[0014] An air outlet is opened at the center of the static disk body, and the static scroll tooth and the movable scroll tooth respectively extend outward in a spiral shape around the air outlet. The involute angle of the static scroll tooth is α1, and the involute angle of the movable scroll tooth is α2. The movable scroll tooth includes a first central area and a first peripheral area, and the static scroll tooth includes a second central area and a second peripheral area. The α1 of any point in the first central area satisfies α1≤540°, and the α2 of any point in the second central area satisfies α2≤540°. The height of the first central area is lower than the height of the first peripheral area to form a first expansion gap between the two, and the height of the second central area is lower than the height of the second peripheral area to form a second expansion gap between the two.

[0015] The side wall of the first central area is provided with a first protective layer outside the protective layer, and the side wall of the second central area is provided with a second protective layer outside the protective layer.

[0016] The wall thickness D1 of the movable scroll tooth in the corresponding first central area is smaller than the wall thickness D2 of the movable scroll tooth in the corresponding first peripheral area, and the thickness M1 of the first protective layer is equal to D2-D1; the wall thickness D3 of the stationary scroll tooth in the corresponding second central area is smaller than the wall thickness D4 of the movable scroll tooth in the corresponding second peripheral area, and the thickness M2 of the second protective layer is equal to D4-D3.

[0017] The first protective layer and the second protective layer are hard oxide films formed by oxidation of the movable scroll and the fixed scroll.

[0018] Due to the adoption of the above technical solution, the beneficial effects achieved by this application are as follows:

[0019] 1. The oil-free scroll air compressor of the present application includes a movable scroll and a stationary scroll, wherein during the eccentric movement of the movable scroll around the stationary scroll, the movable scroll teeth on the movable scroll will engage with the stationary scroll teeth on the stationary scroll, and the air cavity between the movable scroll teeth and the stationary scroll teeth will continue to shrink as the two are relatively engaged, thereby achieving compression of the air in the air cavity; during the eccentric movement of the movable scroll, the movable scroll teeth continuously approach or move away from the stationary scroll teeth, so there is a risk of wear caused by mutual friction between the movable scroll teeth and the stationary scroll teeth. The present application provides a protective layer on the movable scroll and the stationary scroll. When the movable scroll and the stationary scroll come into contact due to being too close, the protective layer can effectively protect the movable scroll and the stationary scroll, prevent the movable scroll and the stationary scroll from rubbing against each other and causing wear, and effectively ensure the structural integrity of the scroll air compressor.

[0020] However, due to the influence of the machining accuracy of the movable scroll and the static scroll, there is an error between the actual movement eccentricity of the movable scroll and the theoretical movement eccentricity. Therefore, it is necessary to reserve a preset gap b between the movable scroll and the static scroll to prevent the two from colliding with each other. After the movable scroll and the static scroll are formed, they also have contours a1 and a2 respectively. The existence of the contours may cause mutual interference when the two are close to each other. The present application sets the thickness D of the protective layer to D=a1+a2+b+c, that is, fully considering the contours of the movable scroll and the static scroll and the actual eccentricity of the movable scroll. When the movable scroll is in the eccentric motion process, the movable scroll is affected by the actual decenteredness and the contours of the movable scroll and the static scroll, resulting in the movable scroll being too close to the static scroll. The protective layer of the present application still has sufficient thickness margin to ensure that the wear caused by the excessive proximity of the movable scroll and the static scroll will not cause the protective layer to be severely damaged and fail to wear out. That is, when the highest point of the outer surface of the movable scroll and the static scroll due to the contour coincides with the deepest point of the movable scroll and the static scroll due to the actual eccentricity error, the protective layer is worn. The thinnest thickness of the worn protective layer is c, which can still effectively protect the movable scroll and the static scroll, thus providing a guarantee for the stable operation of the oil-free scroll air compressor. On this basis, after the movable scroll and the static scroll covered with the protective layer are run-in, the protective layer will be worn away by a part of it, making the outer surface of the movable scroll and the static scroll flat, improving the surface flatness of the movable scroll and the static scroll, and also helping to improve the air compression efficiency of the scroll air compressor.

[0021] 2. As a preferred embodiment of the present application, both the movable scroll and the stationary scroll are made of aluminum alloy. Since the density of aluminum alloy is relatively low, the movable scroll and the stationary scroll made of the aluminum alloy are relatively light, which greatly reduces the weight of the scroll air compressor. Therefore, the oil-free scroll air compressor of the present application can be better applied to small and medium-sized oxygen supply equipment. In addition, since aluminum alloy has good corrosion resistance and good processing performance, the movable scroll and the stationary scroll can also be applied in relatively harsh working environments, while reducing the difficulty of processing and manufacturing the movable scroll and the stationary scroll. Furthermore, the movable scroll and the stationary scroll made of aluminum alloy have good anti-vibration and noise reduction capabilities, which can effectively reduce the outward vibration and noise transmission during the operation of the scroll air compressor.

[0022] On this basis, the protective layer is constructed as a hard oxide film formed by oxidation of the movable scroll and the stationary scroll. On the one hand, the protective layer has good protective performance and can provide adequate protection for the movable scroll and the stationary scroll inside. On the other hand, when the movable scroll wears the stationary scroll during eccentric motion, the protective layer composed of the hard oxide film will be crushed into powder when it is subjected to collision wear, and will not affect the part of the protective layer that is not in contact with each other, thereby preventing the protective layer from falling off due to partial force, and effectively ensuring the integrity of the protective layer. Moreover, the protective layer composed of the hard oxide film can determine the molding thickness of the hard oxide film after the movable scroll and the stationary scroll are manufactured, based on the contour of the movable scroll and the stationary scroll, the preset gap between the movable scroll and the stationary scroll, and the value of the minimum thickness of the protective layer, thereby reducing the difficulty of manufacturing the movable scroll and the stationary scroll.

[0023] 3. As a preferred embodiment of the present application, a first anti-wear gap and a second anti-wear gap are respectively provided at the top of the movable scroll tooth and the static scroll tooth. Since the scroll air compressor is accompanied by the continuous rotation of the movable scroll plate during operation, the temperature of the movable scroll plate and the static scroll plate will increase during operation. Affected by thermal expansion and contraction, wear may easily occur between the movable scroll tooth and the static plate body, and between the static scroll plate and the movable plate body, and there is a risk of serious damage to the protective layer and failure due to wear and tear. The present application provides deformation space for the thermal expansion of the movable scroll tooth and the static scroll tooth by setting the first anti-wear gap and the second anti-wear gap, thereby preventing the protective layer from being worn out due to the thermal expansion of the movable scroll tooth and the static plate body, and the thermal expansion of the static scroll tooth and the movable plate body.

[0024] 4. As a preferred embodiment of the present application, the setting of the first sealing strip and the second sealing strip respectively plays a partial blocking role on the first anti-wear gap and the second anti-wear gap, effectively reducing the leakage of gas from the first anti-wear gap and the second anti-wear gap to the outside, helping to improve the sealing of the scroll air compressor, thereby improving the gas compression effect of the scroll air compressor.

[0025] 5. As a preferred embodiment of the present application, a plurality of first air accommodating grooves and a plurality of second air accommodating grooves are respectively provided on both sides of the first accommodating groove and the second accommodating groove, so that when the gas between the movable scroll gear and the stationary scroll gear enters the first anti-wear gap and the second anti-wear gap, the gas will flow into the plurality of first air accommodating grooves and the second air accommodating grooves. During the movement of the gas entering the first air accommodating groove and the second air accommodating groove, the gas will experience a turning movement, and its kinetic energy will be reduced by the friction between the first air accommodating groove and the second air accommodating groove, and the gas that suffers from the loss of kinetic energy will reduce the probability of escaping and impacting outward. In addition, when the gas enters the first air tank and the second air tank, vortex turbulence will occur due to the sudden change in the direction of movement. The gas will continue to swirl in the first air tank and the second air tank, further reducing the kinetic energy of the gas. The noise generated during the movement of the gas will also be consumed by the blocking and dispersion of the tank arms between the multiple first air tanks and the second air tank, further reducing the probability of air leakage while also reducing the noise transmission to the outside of the scroll air compressor, which helps to improve the noise reduction effect of the scroll air compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0027] Figure 1 An exploded view of an oil-free scroll air compressor according to an embodiment of the present application;

[0028] Figure 2 A top view of a partial structure of an oil-free scroll air compressor according to an embodiment of the present application;

[0029] Figure 3 for Figure 2 A magnified view of part A;

[0030] Figure 4 This is a detailed diagram of the fixed scroll before running-in in one embodiment of the present application;

[0031] Figure 5 This is a detailed diagram of the fixed scroll after running-in in one embodiment of the present application;

[0032] Figure 6 Details of the partial structure of the oil-free scroll air compressor in one embodiment of the present application Figure 1 ;

[0033] Figure 7 Details of the partial structure of the oil-free scroll air compressor in one embodiment of the present application Figure 2 ;

[0034] Figure 8A detailed diagram of a movable scroll tooth according to an embodiment of the present application;

[0035] Fig. 9 A detailed diagram of a fixed scroll tooth according to an embodiment of the present application;

[0036] Fig.10 This is a structural diagram of the movable scroll in the prior art after running for 200 hours;

[0037] Fig.11 This is a structural diagram of the static scroll disk of the present application after running for 10000 hours;

[0038] Fig.12 It is the PQ curve of the oil-free scroll air compressor of this application.

[0039] in:

[0040] 1 movable scroll plate, 11 movable scroll tooth, 111 first accommodating groove, 112 first air accommodating groove, 12 movable plate body;

[0041] 2 static scroll plate, 21 static scroll tooth, 211 second receiving groove, 212 second air receiving groove, 22 static disk body, 221 air outlet;

[0042] 3 protective layers;

[0043] 4The first anti-wear gap;

[0044] 5. Second anti-wear gap;

[0045] 6. The first sealing strip;

[0046] 7 second sealing strip;

[0047] 8 driving parts. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below. It should be noted that the embodiments of the present application and the features in each embodiment may be combined with each other without conflict.

[0050] In addition, in the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0051] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0053] like Figures 1 to 5 As shown, an oil-free scroll air compressor comprises a movable scroll 1 and a stationary scroll 2, the movable scroll 1 comprises a movable scroll body 12 and a movable scroll tooth 11, the stationary scroll 2 comprises a stationary scroll body 22 and a stationary scroll tooth 21, the movable scroll 1 can make an eccentric rotation around the center of the stationary scroll 2 so that the movable scroll tooth 11 makes a meshing motion relative to the stationary scroll tooth 21, the movable scroll 1 and the stationary scroll 2 are respectively provided with a protective layer 3, the thickness of the protective layer 3 is D, the contour of the movable scroll tooth 11 is a1, the contour of the stationary scroll tooth 21 is a2, the preset gap between the meshing points of the movable scroll tooth 11 and the stationary scroll tooth 21 is b, the minimum effective thickness of the protective layer 3 is c, D=a1+a2+b+c; wherein, the service life of the oil-free scroll air compressor is not less than 12000h, and the outlet pressure is not less than 3bar.

[0054] The oil-free scroll air compressor of the present application comprises a movable scroll 1 and a stationary scroll 2, wherein during the eccentric movement of the movable scroll 1 around the stationary scroll 2, the movable scroll teeth 11 on the movable scroll 1 will engage with the stationary scroll teeth 21 on the stationary scroll 2, and the air cavity between the movable scroll teeth 11 and the stationary scroll teeth 21 will continue to shrink as the two are relatively engaged, thereby achieving compression of the air in the air cavity; during the eccentric movement of the movable scroll 1, the movable scroll teeth 11 continue to approach the stationary scroll teeth 21. Or away from the static scroll 21, so the movable scroll 11 and the static scroll 21 are at risk of wear due to mutual friction. The present application provides a protective layer 3 on the movable scroll 1 and the static scroll 2. When the movable scroll 1 and the static scroll 2 are in contact due to being too close, the protective layer 3 can effectively protect the movable scroll 1 and the static scroll 2, preventing the movable scroll 1 and the static scroll 2 from rubbing against each other and causing wear, thereby effectively ensuring the structural integrity of the scroll air compressor. However, due to the influence of the machining accuracy of the movable scroll 1 and the static scroll 2, there is an error between the actual movement eccentricity of the movable scroll 11 and the theoretical movement eccentricity. Therefore, it is necessary to reserve a preset gap b between the movable scroll 11 and the static scroll 21 to prevent the two from colliding with each other. After being formed, the movable scroll 11 and the static scroll 21 also have contours a1 and a2, respectively. The existence of the contours may cause mutual interference when the two are close to each other. The present application sets the thickness D of the protective layer 3 to D=a1+a2+b+c, that is, fully considering the contours of the movable scroll 1 and the stationary scroll 2 and the influence of the actual eccentricity of the movable scroll 1. When the movable scroll 1 is in eccentric motion, the movable scroll tooth 11 is affected by the actual eccentricity and the contours of the movable scroll tooth 11 and the stationary scroll tooth 21. Therefore, even if the movable scroll tooth 11 is too close to the stationary scroll tooth 21, the protective layer 3 of the present application still has sufficient thickness margin to ensure that the wear caused by the excessive proximity of the movable scroll tooth 11 and the stationary scroll tooth 21 will not cause serious damage to the protective layer 3 or even wear through and fail, thereby effectively extending the service life of the scroll air compressor. That is, when the highest point of the outer surface of the movable scroll 11 and the static scroll 21 due to the contour coincides with the deepest point of the overlap between the movable scroll 11 and the static scroll 21 due to the actual eccentricity error, the protective layer 3 is worn. The thinnest thickness of the worn protective layer 3 is c, which can still effectively protect the movable scroll 1 and the static scroll 2, thereby providing a guarantee for the stable operation of the oil-free scroll air compressor. On this basis, after the movable scroll 1 and the static scroll 2 covered with the protective layer 3 are run-in, a part of the protective layer 3 will be worn away, making the outer surfaces of the movable scroll 1 and the static scroll 2 tend to be flat, improving the surface flatness of the movable scroll 1 and the static scroll 2, and also helping to improve the air compression efficiency of the scroll air compressor.

[0055] By controlling the thickness D of the protective layer 3, it is possible to avoid the high point of one of the movable scroll teeth 11 or the static scroll teeth 21 piercing the protective layer due to the thickness being too thin, exposing the substrate, and causing the protective layer to fail; at the same time, it is possible to avoid the increase in processing difficulty due to the excessive thickness of the protective layer 3, resulting in uneven thickness of the protective layer or excessive roughness. At the same time, by controlling the relationship between the thickness D of the protective layer 3, the contour of the movable scroll teeth 11 and the static scroll teeth 21, the preset gap b, and the minimum effective thickness c, the service life of the movable scroll plate 1 and the static scroll plate 2 can be effectively extended, that is, the service life of the compressor can be extended, and the compression capacity of the compressor can be improved.

[0056] like Fig.12 As shown, when the outlet pressure of the compressor continues to increase, its flow rate remains basically unchanged without a significant decrease, indicating that the compressor has good sealing performance between the orbiting scroll 1 and the stationary scroll 2, that is, the compressor has excellent compression capacity.

[0057] Specifically, the oil-free scroll air compressor of the present application is mainly used in small and medium-sized oxygen concentrators. Since the oxygen concentrator has high requirements on the oxygen supply effect and the service life of the scroll air compressor, the service life of the oil-free scroll air compressor of the present application is controlled to be greater than 12000h, and the outlet pressure during operation is not less than 3bar to meet the working requirements of the oxygen concentrator.

[0058] Specifically, due to the influence of processing accuracy, the surface of the protective layer is not an absolutely smooth surface, but a surface with protrusions and depressions. The contour degree in this application is defined as: the height difference between the highest point of the protrusion and the lowest point of the depression on the surface of the protective layer.

[0059] As a preferred embodiment of the present application, the orbiting scroll 1 and the stationary scroll 2 are both made of aluminum alloy material, and the protective layer 3 is constructed as a hard oxide film formed by oxidation of the orbiting scroll 1 and the stationary scroll 2 .

[0060] Since the density of aluminum alloy material is relatively low, the movable scroll 1 and the static scroll 2 made of it are relatively light, which greatly reduces the weight of the scroll air compressor. Therefore, the oil-free scroll air compressor of the present application can be better applied to small and medium-sized oxygen supply equipment; in addition, since aluminum alloy material has good corrosion resistance and good processing performance, the movable scroll 1 and the static scroll 2 can also be applied in relatively harsh working environments, while reducing the difficulty of processing and manufacturing the movable scroll 1 and the static scroll 2. Furthermore, the movable scroll 1 and the static scroll 2 made of aluminum alloy material have good anti-vibration and noise reduction capabilities, which can effectively reduce the outward vibration and noise transmission during the operation of the scroll air compressor. On this basis, the protective layer 3 is constructed as a hard oxide film formed by oxidation of the movable scroll 1 and the fixed scroll 2. On the one hand, the protective layer 3 has good protective performance and can provide sufficient protection for the movable scroll 1 and the fixed scroll 2 inside; on the other hand, when the movable scroll 1 wears the fixed scroll 2 during eccentric motion, the protective layer 3 composed of the hard oxide film will be crushed into powder when it is subjected to collision wear, and will not affect the part of the protective layer 3 that does not have mutual contact and friction, thereby preventing the protective layer 3 from falling off due to partial force, and effectively ensuring the integrity of the protective layer 3. Moreover, the protective layer 3 composed of the hard oxide film can determine the molding thickness of the hard oxide film according to the contour of the movable scroll 1 and the fixed scroll 2, the preset gap between the movable scroll 1 and the fixed scroll 2, and the value of the minimum thickness of the protective layer 3 after the movable scroll 1 and the fixed scroll 2 are manufactured, thereby reducing the difficulty of manufacturing the movable scroll 1 and the fixed scroll 2.

[0061] That is, in this embodiment, the protective layer 3 is not a component that is covered on the fixed scroll 2 and the movable scroll 1 after being manufactured and formed, but the movable scroll 1 and the fixed scroll 2 are first manufactured according to the design size, and then the movable scroll 1 and the fixed scroll 2 are hard anodized to obtain a hard anodized film with a thickness of D as the protective layer 3. Preferably, the aluminum alloy in this embodiment can be an alloy composed of metal aluminum and one or more of metal copper, magnesium, manganese, and silicon.

[0062] As a preferred embodiment of this implementation, Figure 3As shown, the contour a1 of the movable scroll 1 satisfies 5μm≤a1≤20μm, the contour a2 of the fixed scroll 2 satisfies 5μm≤a2≤20μm, the minimum effective thickness c of the protective layer 3 satisfies 5μm≤c≤10μm, and the distance of the preset gap b satisfies 5μm≤b≤20μm. The contours a1 and a2 of the movable scroll 11 and the fixed scroll 21 made of aluminum alloy can generally be controlled in the range of 5μm-20μm, which represents the higher standards that can be achieved in the industry. The thickness c of the protective layer 3 satisfies 5μm≤c≤10μm, which can ensure that the protective layer 3 has sufficient thickness to protect the movable scroll 1 and the fixed scroll 2.

[0063] By controlling the minimum effective thickness c of the protective layer 3, on the one hand, it is ensured that the protective layer still has an effective protective layer thickness after the protrusions of the protective layer are wiped off, and on the other hand, the depressions on the side walls of the movable scroll gear 11 or the static scroll gear 21 can be effectively filled, so that the side wall gap of the scroll plate is uniform, which is conducive to stable performance. By controlling the preset gap b, it is ensured that there is sufficient wear margin between the movable scroll gear 11 and the static scroll gear 21, while ensuring the sealing performance between the two, ensuring that the scroll air compressor has sufficient compression capacity to increase the outlet pressure of the compressor. Preferably, the preset gap b between the meshing point of the movable scroll gear 11 and the static scroll gear 21 is the difference between the actual eccentricity e' and the theoretical eccentricity e when the movable scroll gear 11 performs eccentric motion, that is, b=e'-e.

[0064] Figure 4 L1 in the figure shows the height difference of the protective layer 3 of the fixed scroll disk 2 after hard anodizing. Figure 5 L3 shows the thickness of the protective layer 3 of the static scroll 2 that is worn away after the static scroll 2 and the movable scroll 1 are run-in, and L2 shows the height difference of the protective layer 3 of the static scroll 2 after the movable scroll 1 and the static scroll 2 are run-in. It can be seen that the protective layer 3 of the present application increases the flatness of the outer surface of the static scroll 2 while ensuring sufficient thickness to ensure its own protective effect after running-in; similarly, the same is true for the movable scroll 1, and the protective layer 3 covering its outer surface will also increase the outer surface flatness after running-in, thereby significantly improving the air compression performance of the scroll air compressor.

[0065] As a preferred implementation of the present application, Figure 6 , Figure 7As shown, a first anti-wear gap 4 is provided between the top of the movable scroll 11 and the static disk body 22, and a second anti-wear gap 5 is provided between the top of the static scroll 21 and the movable disk body 12. Since the scroll air compressor is accompanied by the continuous rotation of the movable scroll 1 during operation, the temperature of the movable scroll 1 and the static scroll 2 will increase during operation. Affected by thermal expansion and contraction, it is easy to cause wear between the movable scroll 11 and the static disk body 22, and between the static scroll 2 and the movable disk body 12, and there is a risk of damage and failure of the protective layer 3; the present application provides a deformation space for the thermal expansion of the movable scroll 11 and the static scroll 21 by setting the first anti-wear gap 4 and the second anti-wear gap 5, so as to prevent the wear of the protective layer 3 caused by the thermal expansion of the movable scroll 11 and the static disk body 22, and the thermal expansion of the static scroll 21 and the movable disk body 12.

[0066] As a preferred embodiment of this implementation, Figure 6 , Figure 7 As shown, a first receiving groove 111 is provided at the top of the movable scroll gear 11, a first sealing strip 6 is provided in the first receiving groove 111, and the first sealing strip 6 abuts against the static disk body 22; a second receiving groove 211 is provided at the top of the static scroll gear 21, a second sealing strip 7 is provided in the second receiving groove 211, and the second sealing strip 7 abuts against the movable disk body 12. The provision of the first sealing strip 6 and the second sealing strip 7 respectively partially blocks the first anti-wear gap 4 and the second anti-wear gap 5, effectively reduces the leakage of gas from the first anti-wear gap 4 and the second anti-wear gap 5 to the outside, helps to improve the sealing performance of the scroll air compressor, and thus improves the gas compression effect of the scroll air compressor.

[0067] As a preferred example under this embodiment, Figure 8 , Fig. 9As shown, along the extension direction of the first receiving groove 111, a plurality of first air-containing grooves 112 are arranged at intervals on both sides of the first receiving groove 111 at the top of the movable scroll gear 11; along the extension direction of the second receiving groove 211, a plurality of second air-containing grooves 212 are arranged at intervals on both sides of the second receiving groove 211 at the top of the static scroll gear 21. A plurality of first air-containing grooves 112 and a second air-containing groove 212 are arranged on both sides of the first receiving groove 111 and the second receiving groove 211, respectively. In this way, when the gas between the movable scroll gear 11 and the static scroll gear 21 enters the first anti-wear gap 4 and the second anti-wear gap 5, the gas will flow into the plurality of first air-containing grooves 112 and the second air-containing groove 212. In the process of the gas entering the first air-containing groove 112 and the second air-containing groove 212, the gas will experience a turning motion, and its kinetic energy will be reduced by the friction between the first air-containing groove 112 and the second air-containing groove 212, and the gas that suffers from the loss of kinetic energy will reduce the probability of escaping and impacting outward. In addition, when the gas enters the first air tank 112 and the second air tank 212, vortex turbulence will occur due to the sudden change in the direction of movement. The gas will continue to swirl in the first air tank 112 and the second air tank 212, further reducing the kinetic energy of the gas. The noise generated during the movement of the gas will also be consumed by the blocking and dispersion effect of the tank arms between the multiple first air tanks 112 and the second air tank 212, further reducing the probability of air leakage while also reducing the noise transmission to the outside of the scroll air compressor, which helps to improve the noise reduction effect of the scroll air compressor.

[0068] This embodiment does not limit the manufacturing materials of the first sealing strip 6 and the second sealing strip 7, and they can be any of the following examples:

[0069] Example 1: The first sealing strip 6 is made of modified PTFE material.

[0070] Example 2: The second sealing strip 7 is made of modified PTFE material.

[0071] Example three: The first sealing strip 6 and the second sealing strip 7 are both made of modified PTFE material. The first sealing strip 6 and the second sealing strip 7 made of modified PTFE material have high wear resistance, and their wear damage to the protective layer 3 is small. When the movable scroll gear 11 and the static scroll gear 21 expand due to heat, the increase in volume will cause a certain amount of extrusion to the first sealing strip 6 and the second sealing strip 7, and then push the first sealing strip 6 and the second sealing strip 7 against the static disk body 22 and the movable disk body 12. Since the first sealing strip 6 and the second sealing strip 7 are both made of modified PTFE material, they will not cause excessive wear to the protective layer 3 during the relative movement with the protective layer 3, and effectively ensure the integrity of the protective layer 3 on the movable disk body 12 and the static disk body 22.

[0072] Specifically, the modified PTFE is a modified PTFE material currently available on the market.

[0073] As a preferred implementation of the present application, Figure 2 As shown, an air outlet 221 is provided at the center of the static disk body 22, and the static scroll 21 and the movable scroll 11 extend outward in a spiral shape around the air outlet 221 respectively, the involute angle of the static scroll 21 is α1, and the involute angle of the movable scroll 11 is α2, the movable scroll 11 includes a first central area and a first peripheral area, and the static scroll 21 includes a second central area and a second peripheral area, α1 of any point in the first central area satisfies α1≤540°, and α2 of any point in the second central area satisfies α2≤540°, the height of the first central area is lower than the height of the first peripheral area to form a first expansion gap between the two, and the height of the second central area is lower than the height of the second peripheral area to form a second expansion gap between the two. Since the scroll air compressor generates higher heat during operation, and the closer to the center, that is, the closer to the air outlet 221, the higher the heat, the static scroll 21 and the movable scroll 11 are more susceptible to thermal expansion and deformation in the first central area and the second central area. This embodiment provides a larger deformation space for the movable scroll teeth 11 at the first central area and the stationary scroll teeth 21 at the second central area by setting the first expansion gap and the second expansion gap, thereby reducing the probability of wear between the movable scroll teeth 11 and the stationary scroll teeth 21 and the stationary disk body 22 and the movable disk body 12 respectively caused by thermal deformation.

[0074] As a preferred embodiment of the present embodiment, the side wall of the first central area is provided with a first protective layer outside the protective layer 3, and the side wall of the second central area is provided with a second protective layer outside the protective layer 3. Since the part of the movable scroll 11 corresponding to the first central area and the part of the static scroll 21 corresponding to the second central area are easily deformed by heat, resulting in the side walls being close to each other, by providing the first protective layer and the second protective layer, the probability of the protective layer 3 being damaged due to the movable scroll 11 and the static scroll 21 being too close to each other can be reduced, which helps to maintain the integrity of the protective layer 3.

[0075] Preferably, the wall thickness D1 of the movable scroll 11 in the first central area is smaller than the wall thickness D2 of the movable scroll 11 in the first peripheral area, and the thickness of the first protective layer M1 = D2-D1; the wall thickness D3 of the fixed scroll 21 in the second central area is smaller than the wall thickness D4 of the movable scroll 11 in the second peripheral area, and the thickness of the second protective layer M2 = D4-D3. Such an arrangement provides a larger deformation space for the side walls of the movable scroll 11 and the fixed scroll 21 corresponding to the first central area and the second central area, respectively, and reduces the probability of mutual wear between the first protective layer and the second protective layer of the side wall portion of the movable scroll 11 and the fixed scroll 21 due to thermal deformation.

[0076] As a preferred example in this embodiment, the first protective layer and the second protective layer are hard oxide films formed by oxidation of the orbiting scroll 1 and the fixed scroll 2 .

[0077] The first protective layer and the second protective layer are constructed of hard oxide films formed by oxidation of the movable scroll 1 and the stationary scroll 2. On the one hand, the first protective layer and the second protective layer have good protective performance and can provide adequate protection for the movable scroll 1 and the stationary scroll 2 therein; on the other hand, when the movable scroll 1 wears against the stationary scroll 2 during eccentric motion, the first protective layer and the second protective layer composed of the hard oxide film will be crushed into powder when subjected to collision and wear, without affecting the portions of the first protective layer and the second protective layer that are not in contact and friction with each other, thereby preventing the first protective layer and the second protective layer from falling off due to partial force, thereby effectively ensuring the integrity of the first protective layer and the second protective layer. Moreover, the first protective layer and the second protective layer composed of the hard oxide film can be formed after the movable scroll 1 and the fixed scroll 2 are manufactured, and then the molding thickness of the hard oxide film is determined according to the contour of the movable scroll 1 and the fixed scroll 2, the preset gap between the movable scroll 1 and the fixed scroll 2, and the minimum thickness of the first protective layer and the second protective layer, thereby reducing the difficulty of manufacturing the movable scroll 1 and the fixed scroll 2. In this example, the fixed scroll 2 and the movable scroll 1 are both made of aluminum alloy material, which can be an alloy composed of metal aluminum and one or more of metal copper, magnesium, manganese, and silicon.

[0078] Specifically, the oil-free scroll air compressor in the present application also includes a driving component 8. An air inlet is provided at the edge of the movable scroll 1, and an air outlet 221 is provided at the center of the fixed scroll 2. The driving component 8 can drive the movable scroll 1 to move eccentrically. The air input from the air inlet is compressed by the eccentric movement of the movable scroll 1 and then discharged through the air outlet 221.

[0079] In order to clearly compare the protective effect of the protective layer 3 of the present application on the orbiting scroll 1 and the fixed scroll 2, the present application is based on Fig.10 and Fig.11 For comparison, Fig.10 This is a schematic diagram of the movable scroll in the existing scroll air compressor after running for 200 hours. It can be seen that the movable scroll teeth have obvious wear; Fig.11 This is a schematic diagram of the stationary scroll disk of the scroll air compressor of the present application after running for 10,000 hours. There is no obvious wear on the stationary scroll teeth 21 and the stationary disk body 22, and the protective layer 3 has a significant protective effect.

[0080] Anything not described in this application can be achieved by adopting or drawing on existing technologies.

[0081] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0082] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. An oil-free scroll air compressor, comprising a moving scroll and a fixed scroll, wherein the moving scroll comprises a moving scroll body and a moving scroll tooth, and the fixed scroll comprises a fixed scroll body and a fixed scroll tooth, wherein the moving scroll can rotate eccentrically around the center of the fixed scroll so that the moving scroll tooth meshes with the fixed scroll tooth, and wherein: The movable scroll and the fixed scroll are respectively provided with a protective layer, the thickness of the protective layer is D, the contour of the movable scroll tooth is a1, the contour of the fixed scroll tooth is a2, the preset gap between the meshing points of the movable scroll tooth and the fixed scroll tooth is b, the minimum effective thickness of the protective layer is c, D=a1+a2+b+c; Among them, the service life of the oil-free scroll air compressor is not less than 12000 hours, and the outlet pressure is not less than 3 bar.

2. The oil-free scroll air compressor according to claim 1, characterized in that: The movable scroll and the fixed scroll are both made of aluminum alloy material, and the protective layer is constructed of a hard oxide film formed by oxidation of the movable scroll and the fixed scroll.

3. The oil-free scroll air compressor according to claim 2, characterized in that: The contour a1 of the movable scroll satisfies 5μm≤a1≤20μm, the contour a2 of the stationary scroll satisfies 5μm≤a2≤20μm, the minimum effective thickness c of the protective layer satisfies 5μm≤c≤10μm, and the distance of the preset gap b satisfies 5μm≤b≤20μm.

4. The oil-free scroll air compressor according to claim 1, characterized in that: A first anti-wear gap is provided between the top of the movable scroll gear and the stationary plate body, and a second anti-wear gap is provided between the top of the stationary scroll gear and the movable plate body.

5. The oil-free scroll air compressor according to claim 4, characterized in that: A first receiving groove is provided at the top of the movable scroll gear, a first sealing strip is provided in the first receiving groove, and the first sealing strip abuts against the static disk body; a second receiving groove is provided at the top of the static scroll gear, a second sealing strip is provided in the second receiving groove, and the second sealing strip abuts against the movable disk body.

6. The oil-free scroll air compressor according to claim 5, characterized in that: Along the extension direction of the first accommodating groove, a plurality of first air accommodating grooves are provided at intervals on both sides of the first accommodating groove at the top of the movable scroll tooth; along the extension direction of the second accommodating groove, a plurality of second air accommodating grooves are provided at intervals on both sides of the second accommodating groove at the top of the fixed scroll tooth.

7. The oil-free scroll air compressor according to claim 5, characterized in that: The first sealing strip is made of modified PTFE material, and / or the second sealing strip is made of modified PTFE material.

8. The oil-free scroll air compressor according to claim 1, characterized in that: An air outlet is opened at the center of the static disk body, and the static scroll tooth and the movable scroll tooth respectively extend outward in a spiral shape around the air outlet. The involute angle of the static scroll tooth is α1, and the involute angle of the movable scroll tooth is α2. The movable scroll tooth includes a first central area and a first peripheral area, and the static scroll tooth includes a second central area and a second peripheral area. The α1 of any point in the first central area satisfies α1≤540°, and the α2 of any point in the second central area satisfies α2≤540°. The height of the first central area is lower than the height of the first peripheral area to form a first expansion gap between the two, and the height of the second central area is lower than the height of the second peripheral area to form a second expansion gap between the two.

9. The oil-free scroll air compressor according to claim 8, characterized in that: The side wall of the first central area is provided with a first protective layer outside the protective layer, and the side wall of the second central area is provided with a second protective layer outside the protective layer.

10. The oil-free scroll air compressor according to claim 9, characterized in that: The wall thickness D1 of the movable scroll tooth in the corresponding first central area is smaller than the wall thickness D2 of the movable scroll tooth in the corresponding first peripheral area, and the thickness M1 of the first protective layer is equal to D2-D1; the wall thickness D3 of the stationary scroll tooth in the corresponding second central area is smaller than the wall thickness D4 of the movable scroll tooth in the corresponding second peripheral area, and the thickness M2 of the second protective layer is equal to D4-D3.

11. The oil-free scroll air compressor according to claim 9, characterized in that: The first protective layer and the second protective layer are hard oxide films formed by oxidation of the movable scroll and the fixed scroll.

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