A leak-proof oil-free scroll compressor

Abstract

The present invention relates to a leak-proof oil-free scroll compressor, wherein a plurality of magnet seats are arranged on the lower shell of the compressor, a first annular magnet is arranged on the plurality of magnet seats, the first annular magnet is arranged opposite to the second annular magnet, the first annular magnet and the second annular magnet have mutually repelling magnetic forces, the second annular magnet is fixed to a suspension platform, an armature is fixed to the suspension platform, a movable scroll is fixed above the armature, a stationary scroll is embedded above the movable scroll, the stationary scroll is fixedly connected to an upper plate, and the upper plate and the lower shell together form a cavity; along the inner wall around the lower shell, U-shaped electromagnets are fixedly arranged on the lower shell, the U-shaped electromagnets are arranged opposite to each other in pairs, and the U-shaped electromagnets surround the armature. The present invention solves the problems of bearing and anti-rotation mechanism lubrication, the problem of axial clearance not being able to be automatically eliminated, the problem of automatic adjustment of gyration radius and displacement control, gas leakage, etc. existing in the existing oil-free scroll compressor.

Description

Technical Field

[0001] The invention relates to the technical field of compressors, and in particular to a magnetically driven, leak-proof, oil-free scroll compressor capable of automatically adjusting a gyration radius. Background Art

[0002] At present, all scroll compressors on the market are driven by the electric spindle and then converted into the translation of the scroll by the anti-self-rotation device. The lower end of the electric spindle is an oil reservoir. The oil circuit of the oil reservoir is an oil tank at the center of the electric spindle. The oil supply method is achieved through the upper and lower pressure difference of the scroll compressor. The bearings and anti-self-rotation mechanisms in the scroll compressor need to be lubricated. With the continuous development of scroll compressors, more and more fields (such as food, medical care, fuel cells, etc.) require clean, oil-free and clean gas. In order to save energy and meet market demand, the market has replaced the bearings that need to be lubricated with self-lubricating bearings on the basis of fully enclosed scroll compressors, removed the oil reservoir on the original scroll compressor, and coated the anti-self-rotation mechanism with a layer of self-lubricating material at the position where it contacts the movable scroll and the casing. The process of applying the self-lubricating material is generally: sandblasting-cleaning-hard anodizing-cleaning-spraying-sintering. Its process is complex and has low precision. Although the oil-free scroll compressor of this structure has achieved the purpose of being oil-free, there are new problems in friction, life and heat generation. The scroll compressor mainly includes components such as the static disk, the dynamic disk, the anti-rotation mechanism, the bracket body and the transmission mechanism. The two scroll teeth of the compressor form a crescent-shaped volume cavity. As the crankshaft rotates continuously, the scroll teeth meshing process causes wear and deformation under the pressure difference force and high temperature. The scroll disk processing accuracy cannot meet the requirements. These factors can cause radial and axial gaps between the dynamic and static scroll teeth, forming circumferential and radial leakage respectively, affecting the working efficiency of the compressor. Since the leakage line is longer, the leakage of the axial gap has a more serious impact. Sealing strips are generally used in the market to reduce leakage by expanding the sealing strips. The sealing strips are generally made of polytetrafluoroethylene. As the wear and tear increases, the leakage will become larger and larger, and the sealing strips need to be replaced. It is not suitable for occasions that require long-term continuous work. The scroll disk processing accuracy requirements of the scroll compressor are very high. The tooth thickness of the profile line is often not always equal during actual processing, and there will be small protrusions. The scroll disks will cause serious wear due to the fitting movement. In the past, a new automatic eccentricity adjustment mechanism was added, which was available in slider type and elastic type. Both mechanisms had a 3 to 5 micron telescopic margin. When encountering a raised scroll, the scroll would retract and immediately reset.

[0003] This scroll compressor does not require additional adjustment devices. The magnetic force is a non-contact force that can automatically adjust the radius of motion of the moving scroll. Traditional air-conditioning compressors rely on their continuous "on and off" to adjust the indoor temperature. The on and off time can easily cause the room temperature to fluctuate and consume a lot of electricity. Inverter air conditioners are mostly used on the market, which rely on the speed of the air-conditioning compressor to achieve the purpose of controlling the room temperature. The room temperature fluctuates less, consumes less electricity, and its comfort is greatly improved. However, the circuit control board components of the inverter system have thousands of parts, and the circuits are complex and numerous. Therefore, the probability of circuit board failure is much greater than that of simple non-inverter compression.

[0004] In summary, existing oil-free scroll compressors have problems with lubrication of bearings and anti-rotation mechanisms, the inability to automatically eliminate axial clearance, the automatic adjustment of the gyration radius, the displacement control, and gas leakage. Summary of the invention

[0005] Purpose of the invention: The present invention proposes a leakage-proof oil-free scroll compressor, which aims to solve the problems of lubrication of bearings and anti-rotation mechanisms, the problem of inability to automatically eliminate axial clearance, the problem of automatic adjustment of the rotation radius and displacement control, and the problem of gas leakage in existing oil-free scroll compressors.

[0006] Technical solution:

[0007] A leak-proof oil-free scroll compressor, wherein a plurality of magnet seats are arranged on the bottom plate of the lower shell of the compressor, a first annular magnet is arranged correspondingly on the plurality of magnet seats, the first annular magnet and the second annular magnet are arranged oppositely, the first annular magnet and the second annular magnet repel each other magnetically, the second annular magnet is fixed to the lower surface of a suspension platform, an armature is fixed to the upper surface of the suspension platform, a movable scroll is fixed above the armature, a static scroll is embedded above the movable scroll, an internal cavity is formed between the static scroll and the movable scroll, the static scroll is fixedly connected to the upper plate, and the upper plate and the lower shell together form a cavity; a plurality of U-shaped electromagnets are fixedly arranged on the lower shell along the inner wall around the lower shell, the plurality of U-shaped electromagnets are arranged oppositely in pairs, the plurality of U-shaped electromagnets surround the armature, and the armature is in the middle position; a protective ring is also arranged on the bottom plate of the lower shell, there is a gap δ between the protective ring and the suspension platform, a bracket is fixed on the protective ring, and a sensor is installed on the bracket.

[0008] The silicon steel sheet of the U-shaped electromagnet is in U shape, and the coil is arranged on the vertical side of the U shape, and the coils arranged on the opposite set of U-shaped electromagnets are also corresponding.

[0009] The U-shaped electromagnet includes a first U-shaped electromagnet and a second U-shaped electromagnet. There are two first U-shaped electromagnets, which are relatively arranged on the front and rear sides of the armature, and coils are arranged on the two vertical sides of the U shape of the first U-shaped electromagnet; there are four second U-shaped electromagnets, which are relatively arranged on the left and right sides of the armature in pairs, and coils are arranged on the outer vertical sides of the U shapes of two adjacent second U-shaped electromagnets.

[0010] The number of the magnet seat, the first annular magnet and the second annular magnet are all set to four, and it is ensured that the first annular magnet and the second annular magnet are arranged opposite to each other.

[0011] The second annular magnets are arranged at the four corners of the suspension platform.

[0012] The armature is a square frame structure, which is composed of a plurality of square frame structures of silicon steel sheets stacked together.

[0013] The gap δ is consistent with the length of the orbit radius of the movable scroll.

[0014] The material of the movable scroll is polytetrafluoroethylene, and the mass of the movable scroll is smaller than that of the fixed scroll.

[0015] The protective ring is a solid structure made of polytetrafluoroethylene material.

[0016] Advantages and effects:

[0017] The present invention provides a leakage-proof oil-free scroll compressor which is driven by magnetic force and can automatically adjust the turning radius. The magnetic levitation technology is used as the driving force to solve the lubrication problems of bearings and anti-rotation mechanisms in the existing oil-free scroll compressor, the problem that the axial gap cannot be automatically eliminated, the problem of automatic adjustment of the turning radius and the problem of displacement control, and the problem of gas leakage. At the same time, the active control of the electromagnetic force can also make the radial contact force between the movable scroll and the stationary scroll be maintained within a certain range, so as to reduce the friction between the movable scroll and the stationary scroll.

[0018] The invention has a simple structure, no wearing parts, can work continuously for a long time, has light weight, low noise, low energy consumption, long service life, low speed limitation requirements, and is safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of the front view of the scroll compressor;

[0020] Figure 2 is a cross-sectional view of a scroll compressor from above;

[0021] Figure 3 It is a schematic diagram of the overall structure of a scroll compressor;

[0022] Figure 4 It is a schematic diagram of the structure of the suspension platform and the annular magnet of the scroll compressor;

[0023] Figure 5 is the compression force Fy of the compressor's armature in the front-rear direction;

[0024] Figure 6 is the compression force Fx of the compressor's armature in the left and right directions;

[0025] Figure 7 is the theoretical calculated value of the relationship between compressor force and rotation angle;

[0026] Figure 8 Magnetic simulation data provided for the magnetic energy of small electromagnets;

[0027] Reference numerals:

[0028] 1. static scroll, 2. upper plate, 3. movable scroll, 4. U-shaped electromagnet, 41. first U-shaped electromagnet, 42. second U-shaped electromagnet, 5. armature, 6. electromagnet bracket, 7. bracket, 8. second annular magnet, 9. sensor, 10. protection ring, 11. magnet seat, 12. first annular magnet, 13. suspension platform, 14. lower shell, 15. coil. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the accompanying drawings. Figure 3 The direction of the upper and lower parts shown in the figure; the left and right parts described in the figure are as shown in the figure Figure 3 Left and right directions shown.

[0030] like Figure 1 , 2 As shown in Figure 4, a leak-proof oil-free scroll compressor is provided with a plurality of magnet seats 11 on the bottom plate of the lower shell 14 of the compressor, and four first annular magnets 12 are correspondingly provided on the plurality of magnet seats 11, and the first annular magnet 12 is arranged opposite to the second annular magnet 8, and the first annular magnet 12 and the second annular magnet 8 have completely the same structure, but when fixed, the first annular magnet 12 and the second annular magnet 8 are magnetically repelled from each other to form a magnetic suspension structure, and the first annular magnet 12 and the second annular magnet 8 form an axial automatic adjustment device, and if there is vibration, the gap between the teeth and the disk surface of the movable scroll 3 and the fixed scroll 1 can be supplemented to reduce gas leakage. The vibration pushes outward in the radial direction, and the magnetic force is perpendicular to the movement trajectory of the movable scroll 3, and the fixed scroll 1 and the movable scroll 3 form a sealing device, which greatly reduces gas leakage. Thus, the lubrication problem of the bearings and the anti-rotation mechanism in the existing oil-free scroll compressor and the problem that the axial gap cannot be automatically eliminated are solved.

[0031] The material of the movable scroll 3 is polytetrafluoroethylene. Existing scrolls generally use aluminum alloys and cast iron. The materials of the movable and static scrolls of this compressor are different. The static scroll 1 is made of aluminum alloy, and the movable scroll 3 is made of polytetrafluoroethylene, which is lighter and reduces power waste. The static scroll 1 has to withstand more impacts and friction, so the strength and hardness of the static scroll 1 are higher than those of the movable scroll 3. When the movable scroll is subjected to high temperature, it will expand slightly to fill the gap on the end face of the scroll tooth and reduce gas leakage. The movable scroll 3 of the present invention does not have grooves on the end face and sealing strips. The traditional movable scroll 3 is made of aluminum alloy, and grooves are added to the end face of the scroll and sealing strips are added to reduce gas leakage and friction. The movable scroll 3 designed by the present invention does not require a sealing strip, and the material itself has a low friction coefficient.

[0032] The armature 5 is a square frame structure, which is made of a plurality of silicon steel sheets stacked in a square frame structure. The square frame can reduce weight and power consumption, and the whole is more convenient for positioning than four separate pieces. The armature is made of stacked silicon steel sheets instead of a whole iron core to prevent the formation of eddy currents and excessive heating.

[0033] like Figure 3 As shown, the U-shaped electromagnet 4 of the present invention is set to six in total, and the U-shaped electromagnet 4 is fixed on the electromagnet bracket 6 on the bottom plate of the lower shell 14. The U-shaped electromagnet 4 is arranged opposite to each other in pairs, and the middle position surrounded is the armature 5 that needs to be attracted. The six U-shaped electromagnets 4 control three degrees of freedom in the plane, which can suppress the rotation of the movable scroll and form an anti-rotation device. The electromagnets on both sides of the movable scroll attract each other with a certain rigidity. The thickness of the iron core of the U-shaped electromagnet 4 does not exceed the thickness of the armature 5, which reduces the space volume and magnetic force waste. The U-shaped electromagnet 4 includes a first U-shaped electromagnet 41 and a second U-shaped electromagnet 42. The first U-shaped electromagnet 41 is two, which are relatively arranged on the front and rear sides of the armature 5. The first U-shaped electromagnet 41 has two U-shaped vertical sides, which provide greater power with less volume and make full use of the magnetic force of the first U-shaped electromagnet 41. The second U-shaped electromagnet 42 is four, which are relatively arranged on the left and right sides of the armature 5 in pairs, and the outer vertical sides of the U-shaped adjacent two second U-shaped electromagnets 42 are provided with coils 15. Two second U-shaped electromagnets 42 are arranged on the left and right sides of the armature 5, respectively, which can control one more degree of freedom, thereby inhibiting the rotation of the movable scroll 3, avoiding the use of an anti-rotation device, reducing friction and impact, and thus achieving oil-free operation. Wrapping the coil 15 on the outside of the second U-shaped electromagnet 42 makes the space utilization rate higher and the structure more compact. When the coil 15 is wrapped on the outside, the magnetic force on the outside is greater, which is more conducive to controlling the rotation.

[0034] like Figure 4As shown, the second annular magnet 8 is fixed on the four corners of the lower surface of the suspension platform 13. The four pairs of magnets at the four corners are evenly stressed and more stable, and the axial displacement caused by vibration can be supplemented at the four corners. The armature 5 is bolted fixedly connected at the edge of the upper surface of the suspension platform 13. The movable scroll 3 is arranged above the armature 5. The static scroll 1 is embedded above the movable scroll 3. An internal cavity is formed between the static scroll 1 and the movable scroll 3. The static scroll 1 is fixedly connected to the upper plate 2 by screws. The upper plate 2 and the lower shell 14 form a cavity structure together; along the inner wall around the lower shell 14, a plurality of U-shaped electromagnets 4 are fixedly arranged on the bottom plate of the lower shell 14. The plurality of U-shaped electromagnets 4 are arranged opposite to each other in pairs. The plurality of U-shaped electromagnets 4 surround the armature 5, and the armature 5 is in the middle position; a protective ring 10 is also arranged on the bottom plate of the lower shell 14, and a bracket 7 is fixed on the protective ring 10, and a sensor 9 is installed on the bracket 7.

[0035] The protective ring 10 is a solid structure made of polytetrafluoroethylene. Polytetrafluoroethylene has excellent heat and cold resistance, extremely low friction coefficient and smooth surface. Moreover, the solid (core) structure is not afraid of impact, and can limit the movement range of the movable scroll 3. When out of control occurs, the movable scroll 3 will hit the protective ring 10, thereby preventing the fixed scroll 1 and the U-shaped electromagnet 4 from being damaged in the event of out of control. There is a gap δ between the protective ring 10 and the suspension platform 13, and the gap δ is consistent with the length of the radius of the running trajectory of the movable scroll 3. It is preferably 2mm. If the movable scroll 3 is out of control, it will hit the protective ring 10, and the movable scroll 3 will not damage the teeth of the fixed scroll 1 and / or the movable scroll 3, which has a protective effect on the teeth of the fixed scroll 1 and the movable scroll 3.

[0036] A bracket 7 is fixed on the protective ring 10, and three sensors 9 are installed on the bracket 7. The sensor 9 is used to measure the distance between the U-shaped electromagnet 4 and the armature 5. The distance between the two is measured in order to control the position of the movable scroll 3 through the U-shaped electromagnet 4. The U-shaped electromagnet 4 controls the movement trajectory of the movable scroll 3 to always be a circle, and the teeth of the movable scroll 3 and the teeth of the fixed scroll 1 are always in contact with each other to prevent air leakage. Two sensors 9 are relatively arranged on the bracket 7, and are used to measure the distance between the armature 5 and the U-shaped electromagnets 4 on the left and right sides of the armature 5, and control the measured distance values ​​to be the same, and inhibit the rotation of the movable scroll 3; another sensor 9 is used to measure the distance between the armature 5 and the U-shaped electromagnets 4 on the front and rear sides of the armature 5. In the longitudinal direction, the four pairs of first annular magnets 12 and second annular magnets 8 repel each other, so that the end face of the movable scroll 3 always fits the surface of the fixed scroll 1.

[0037] The inner side of the scroll wall of the scroll disk is generally processed by milling to form a scroll surface. The convex and concave points formed by machining errors will increase gas leakage and even aggravate the wear between the scroll disks. Figure 1 and Figure 3As shown, the protective ring 10 and the U-shaped electromagnet 4 form an automatic adjustment device for the gyration radius. If the vortex body is thick, the orbit radius of the movable scroll can be reduced to avoid collision and excessive wear. If the vortex body is thin, the orbit radius of the movable scroll can be increased to make the teeth of the scroll always fit closely to reduce leakage. This makes up for the processing error of the vortex body wall thickness and can reduce or eliminate the effect of abnormal load.

[0038] The electromagnet 4 drives the movable scroll 3, and the running trajectory of the movable scroll 3 is actively controlled. The moving radius of the movable scroll 3 is controlled by the electromagnet 4. Reducing the trajectory radius can increase the radial gap and cause serious leakage. The gas cannot be compressed and the compressor enters the standby state, thereby realizing stepless adjustment of the compressor displacement.

[0039] like Figure 5-8 As shown, the data of the scroll compressor of the present invention. Figures 5 to 7 The data comes from theoretical calculations, and the formula is referenced from "Scroll Fluid Machinery and Scroll Compressors". Figure 8 From ansoft software simulation.

[0040] from Figure 8 The electromagnetic force diagram shows that within the range of 0.5mm to 3.0mm, the magnetically driven scroll compressor can provide a maximum force of 118N to 367N. Figure 8 The data comes from the magnetic force simulation of a small electromagnet. The magnetic force of a large electromagnet is much greater than this, so it can meet the needs of the compressor. Figure 7 As shown, Figure 7 The data from "Scroll Fluid Machinery and Scroll Compressors" shows the three most important and basic forces of scroll compressors: axial force, radial force and tangential force. Figure 5 and Figure 6 The radial force and tangential force are decomposed into the x and y axes to deduce the force required to drive the scroll compressor, providing a theoretical basis for the design. Figure 5 and Figure 6 As shown in the figure, the maximum force required for the compressor to operate is 92 N, so the drive element fully meets the driving force requirements. As the air gap increases, the magnetic force decreases rapidly, limiting the range of motion of the scroll and ultimately limiting the displacement of the scroll compressor under magnetic drive.

[0041] The present invention has a certain flexibility of movement, is free of lubricating oil, and uses magnetic levitation technology as a driving force to solve the lubrication problems of bearings and anti-rotation mechanisms in existing oil-free scroll compressors, the problem that axial clearance cannot be automatically eliminated, the problem of automatic adjustment of the rotation radius, and the problem of displacement control. At the same time, through the active control of electromagnetic force, the contact force between the movable scroll and the stationary scroll can be maintained within a certain range to reduce the friction between the movable scroll and the stationary scroll.

Claims

1. A leak-proof oil-free scroll compressor, characterized in that: A plurality of magnet seats (11) are arranged on the bottom plate of the lower shell (14) of the compressor, a first annular magnet (12) is arranged correspondingly on the plurality of magnet seats (11), the first annular magnet (12) and the second annular magnet (8) are arranged opposite to each other, the first annular magnet (12) and the second annular magnet (8) have mutually repelling magnetic forces, the second annular magnet (8) is fixed to the lower surface of the suspension platform (13), an armature (5) is fixed to the upper surface of the suspension platform (13), a movable scroll (3) is fixed above the armature (5), a stationary scroll (1) is embedded above the movable scroll (3), and an internal cavity is formed between the stationary scroll (1) and the movable scroll (3) The static vortex disk (1) is fixedly connected to the upper plate (2), and the upper plate (2) and the lower shell (14) together form a cavity; a plurality of U-shaped electromagnets (4) are fixedly arranged on the lower shell (14) along the inner wall around the lower shell (14), and the plurality of U-shaped electromagnets (4) are arranged opposite to each other in pairs, and the plurality of U-shaped electromagnets (4) surround the armature (5), and the armature (5) is in the middle position; a protective ring (10) is also arranged on the bottom plate of the lower shell (14), and there is a gap δ between the protective ring (10) and the suspension platform (13), and a bracket (7) is fixed on the protective ring (10), and a sensor (9) is installed on the bracket (7); The silicon steel sheet of the U-shaped electromagnet (4) is in a U-shape, and the coil (15) is arranged on the vertical side of the U-shape, and the coils (15) arranged on the opposite set of U-shaped electromagnets (4) are also corresponding; The U-shaped electromagnet (4) comprises a first U-shaped electromagnet (41) and a second U-shaped electromagnet (42), wherein the first U-shaped electromagnet (41) is two and is arranged on the front and rear sides of the armature (5) in a relative manner, and the two vertical sides of the U-shape of the first U-shaped electromagnet (41) are both provided with a coil (15); the second U-shaped electromagnet (42) is four and is arranged on the left and right sides of the armature (5) in pairs in a relative manner, and the outer vertical sides of the U-shape of two adjacent second U-shaped electromagnets (42) are provided with a coil (15); The number of the magnet seat (11), the first annular magnet (12) and the second annular magnet (8) is set to four, and the first annular magnet (12) and the second annular magnet (8) are ensured to be arranged relative to each other; The second annular magnets (8) are arranged at the four corners of the suspension platform (13); The material of the movable scroll (3) is polytetrafluoroethylene, and the mass of the movable scroll (3) is smaller than the mass of the stationary scroll (1); The armature (5) is a square frame structure, which is formed by stacking a plurality of silicon steel sheets of square frame structures; The gap δ is consistent with the length of the radius of the orbital trajectory of the movable scroll (3).

2. The anti-leakage oil-free scroll compressor according to claim 1, characterized in that: The protection ring (10) is a solid structure made of polytetrafluoroethylene material.

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