Low-pulsation oil injection scroll compressor static scroll plate and scroll compressor

Abstract

The invention relates to the field of scroll compressors, in particular to a low-pulsation oil injection scroll compressor static scroll plate and a scroll compressor, and an oil injection mechanism comprises a first oil injection channel and a second oil injection channel which are arranged in the static scroll plate. The first oil injection channel is connected with a first oil injection hole and a second oil injection hole, and openings of the first oil injection channel and the second oil injection hole are formed in the outer side of the molded line of the static scroll plate; the second oil injection channel is connected with a third oil injection hole and a fourth oil injection hole, and an opening is formed in the inner side of the molded line of the static scroll plate. In the air inlet stage, when the first compression cavity and the second compression cavity are formed, oil injection cooling is started through the first oil injection hole and the fourth oil injection hole; and in the exhaust stage, before the first compression cavity and the second compression cavity are communicated with the exhaust port, the second oil injection hole and the third oil injection hole are sequentially closed. The oil injection process covers the whole compression process of the gas, so that the cooling efficiency of the compressed gas is greatly improved, the vibration of the oil injection system is reduced, the noise is reduced, and the stability of the oil injection system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of scroll compressors, and particularly relates to a static scroll plate of a low-pulsation oil-injected scroll compressor and a scroll compressor. Background Art

[0002] A scroll compressor is composed of a fixed involute scroll plate and an involute moving scroll plate that performs eccentric rotary translation to form a compressible volume. Gas is inhaled from the periphery of the static scroll plate. As the eccentric shaft rotates, the gas is gradually compressed in several crescent-shaped compression chambers formed by the meshing of the moving and static scroll plates, and then continuously discharged through the axial holes of the central component of the static plate.

[0003] In a scroll compressor for helium, the heat is relatively large after helium compression, and the exhaust temperature of the compressor is high, resulting in carbonization of the lubricating oil and the inability of the compressor to operate stably.

[0004] In the prior art, for example, in a hermetic scroll compressor for helium with the patent number CN201210148686.X, an oil injection port is opened at the bottom of the fixed scroll plate, and a long hole shape with a length dimension greater than the width dimension of the rotating scroll plate (i.e., L7 > t) is provided at its opening to achieve oil injection into two compression chambers for cooling purposes. However, this structural design has the following defects: 1. A single oil injection hole cannot be used for a symmetric scroll design, and when applied to an asymmetric scroll, the maximum opening rotation angle is 360°, and for the subsequent compression process, oil injection cooling cannot be performed. 2. Oil is already being injected into the outer line chamber suction cavity at an angle θ5 before it closes. Since the oil injection temperature is generally higher than the suction temperature, the oil injection will preheat the helium, which is harmful to cooling the helium and will also cause suction pressure pulsation. 3. Its main purpose is to balance the pressure difference between the two chambers through the oil injection setting, but while the pressure is balanced, there is a large difference in the oil injection amounts of the two chambers, which will lead to a large difference in the oil injection amounts of the two chambers.

[0005] For example, in an oil injection cooling structure for a hermetic scroll compressor for helium with the application number CN202410130686.X, two oil injection holes are provided, and the two oil injection holes are separately connected to the compression chambers. The oil injection holes will be blocked by the rotating scroll teeth during the scroll operation, resulting in intermittent oil injection. In this design, during actual use, the oil injection passage is continuously opened and closed, and the pulsation formed by the oil injection pressure is transmitted to the system pipeline, causing large vibrations in the oil injection pipeline, resulting in noise and affecting the strength of the pipeline system in the long term.

[0006] For a stationary scroll plate and a scroll compressor of an oil-injected scroll compressor with the patent number CN202310625628.X, by providing two or more oil injection structures, oil injection cooling for two compression chambers is achieved. However, such a structural arrangement has the following defects: 1. When the moving scroll plate and the stationary scroll plate are engaged, it is a line contact. Grooving on the side wall of the stationary scroll tooth will cause the stationary scroll plate and the moving scroll plate to not be tightly engaged, resulting in radial leakage of gas and reduced compression efficiency; 2. According to the setting of the first oil injection part 130 and the positions of the holes 131 and 132, the hole 132 is arranged inside the involute of the stationary scroll plate, and the hole 131 is arranged outside the involute of the stationary scroll plate. Inevitably, before the intake stage and before the compression chamber is formed, the holes 131 and 132 are already injecting oil, causing fluctuations in the intake pressure; and the hole positions are arranged close to the intake port. Oil is injected at the intake port before the compression chamber is closed. At this time, the oil injection temperature is higher than the intake temperature, causing the oil injection to preheat the gas, which is not conducive to the cooling of compressed helium; 3. The setting of two or more oil inlet channels for the first oil injection part 130 and the second oil injection part 140 will have different oil injection pressures, and separate oil injection control is required, resulting in complex oil injection control; 4. Setting deep holes on the scroll teeth will cause the strength of the scroll teeth to decrease, and there is a risk of fracture during long-term use. In addition, the width of the scroll teeth is small, and the processing difficulty of deep holes is large, which will cause a substantial increase in cost in practical applications.

[0007] Therefore, how to perform refined control on the oil injection cooling of the scroll compressor to ensure the stable operation of the compression equipment while improving the cooling capacity is an issue that those skilled in the art need to consider. Summary of the Invention

[0008] The object of the present invention is to provide a stationary scroll plate and a scroll compressor of a low-pulsation oil-injected scroll compressor to solve the problems of large oil injection pulsation, poor cooling effect of compressed gas, and uneven cooling of each chamber in the prior art.

[0009] The technical solution of the present invention is: A stationary scroll plate of a low-pulsation oil-injected scroll compressor, the stationary scroll plate includes an exhaust port and an oil injection mechanism, the moving scroll plate includes moving scroll teeth, the first compression chamber and the second compression chamber formed by the engagement of the stationary scroll plate and the moving scroll plate, the oil injection mechanism includes a first oil injection channel and a second oil injection channel arranged inside the stationary scroll plate, and the first oil injection channel and the second oil injection channel are simultaneously connected to an oil inlet pipe; The first oil injection channel is connected with a first oil injection hole and a second oil injection hole, and the openings are both arranged outside the involute of the stationary scroll plate; the second oil injection channel is connected with a third oil injection hole and a fourth oil injection hole, and the openings are arranged inside the involute of the stationary scroll plate; During the intake stage, the overlapping areas of the first fuel injection hole and the fourth fuel injection hole with the moving scroll teeth gradually decrease, and the opening degrees gradually increase, respectively having a tendency to communicate with the first compression chamber and the second compression chamber and the communicating area becoming larger; during the exhaust stage, the overlapping areas of the second fuel injection hole and the third fuel injection hole with the moving scroll teeth gradually increase, and the opening degrees gradually decrease, respectively having a tendency to close with the first compression chamber and the second compression chamber and the closing area increasing.

[0010] Preferably, the first oil injection passage and the second oil inlet passage are arranged in a V shape, and the intersection is simultaneously communicated with the oil inlet pipe.

[0011] Preferably, the oil inlet pipe is connected to the side of the stationary scroll plate.

[0012] Preferably, the apertures of the first fuel injection hole, the second fuel injection hole, the third fuel injection hole and the fourth fuel injection hole are the same and smaller than the width of the moving scroll teeth.

[0013] Preferably, the distances between the first fuel injection hole and the second fuel injection hole and the outer wall of the stationary scroll teeth of the stationary scroll plate are greater than 0; the distances between the third fuel injection hole and the fourth fuel injection hole and the inner wall of the stationary scroll teeth are greater than 0.

[0014] A scroll compressor applies a stationary scroll plate of a low-pulsation fuel injection scroll compressor.

[0015] Compared with the prior art, the advantages of the present invention are: (1) During the intake stage, when the first compression chamber and the second compression chamber are formed, fuel injection cooling starts respectively through the first fuel injection hole and the fourth fuel injection hole; during the exhaust stage, before the first compression chamber and the second compression chamber are communicated with the exhaust port, the second fuel injection hole and the third fuel injection hole are closed in sequence. The fuel injection process covers the entire compression process of the gas, continuously performs fuel injection cooling, and greatly improves the cooling efficiency of the compressed gas; In addition, before the compression chamber is formed, it is in a state of not fuel injecting or just starting to fuel inject, and after the compressed gas is exhausted, the gas is no longer cooled, realizing the fine control of fuel injection cooling and optimizing the compression and cooling efficiency; (2) The sequence of connection and closing of the four fuel injection holes is as follows: the first fuel injection hole and the fourth fuel injection hole are opened first, that is, the first oil injection passage is communicated with the first compression chamber, and the second oil injection passage is communicated with the second compression chamber. Both compression chambers are in the initial stage, and the pressures borne by the two oil injection passages are basically the same. Therefore, the pressures in the two compression chambers are in a dynamic equilibrium state, avoiding pressure fluctuations; before they are closed, the second fuel injection hole and the third fuel injection hole are opened in sequence. That is, the first oil injection passage and the second oil injection passage are always in a state of oil flow, continuously fuel injecting, increasing the cooling efficiency of the compressed gas; greatly reducing the pulsation of the fuel injection pressure, thereby reducing the vibration of the fuel injection system, reducing noise, and improving the stability of the fuel injection system; Moreover, the two oil injection channels are cross-connected and are simultaneously connected to the oil inlet pipe, making the oil passage smoother, reducing the flow resistance, and further reducing the pulsation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the drawings and embodiments: Figure 1 is a schematic structural diagram of the compression mechanism of the scroll compressor according to the present invention; Figure 2 is a schematic structural diagram of the oil injection mechanism according to the present invention; Figure 3 is a schematic structural diagram of the stationary scroll plate according to the present invention; Figure 4-1 is a schematic structural diagram when the first compression chamber and the second compression chamber are formed in the intake stage according to the present invention; Figure 4-2 is a schematic structural diagram of the compression stage according to the present invention Figure 1 ; Figure 4-3 is a schematic structural diagram of the compression stage according to the present invention Figure 2 ; Figure 4-4 is a schematic structural diagram when the second compression chamber is communicated with the exhaust port in the exhaust stage according to the present invention; Figure 4-5 is a schematic structural diagram when the first compression chamber is communicated with the exhaust port in the exhaust stage according to the present invention; Figure 5 is a schematic diagram of the opening situation of the oil injection holes when the moving scroll plate is at different angles after the two compression chambers are closed according to the present invention.

[0017] Wherein: moving scroll plate 1, moving scroll teeth 11; stationary scroll plate 2, air inlet 21, exhaust port 22, stationary scroll teeth 23, first compression chamber 24, second compression chamber 25; oil injection mechanism 3, first oil injection channel 31, first oil injection hole 311, second oil injection hole 312, second oil injection channel 32, third oil injection hole 321, fourth oil injection hole 322, oil inlet pipe 33. DETAILED DESCRIPTION OF THE INVENTION

[0018] The content of the present invention will be further described in detail below in conjunction with specific embodiments: As Figures 1-3As shown, the present invention is applied to a scroll compressor device in gas compression such as helium. It includes a moving scroll disk 1 and a stationary scroll disk 2. An air inlet 21 and an air outlet 22 are provided on the stationary scroll disk 2. When the compressor works, the moving scroll disk 1 translates relative to the stationary scroll disk 2 to form a first compression chamber 24 and a second compression chamber 25. As the translation progresses, the volumes of the first compression chamber 24 and the second compression chamber 25 become smaller, and the gas is gradually compressed. Finally, it communicates with the air outlet 22 in sequence to discharge the compressed gas. During this process, heat is generated due to the relative meshing movement between the moving scroll disk 1 and the stationary scroll disk 2. At the same time, a large amount of heat is also generated during the compression of the gas, resulting in an increase in the temperature of the compression mechanism and the gas. Therefore, in this embodiment, corresponding oil injection channels are provided on the stationary scroll disk 2 to continuously cool the compressed gas during the gas compression process to reduce the exhaust temperature and to cool and lubricate the compression mechanism.

[0019] Specifically: The oil injection mechanism 3 includes a first oil injection channel 31 and a second oil injection channel 32 provided inside the stationary scroll disk 2. The first oil injection channel 31 and the second oil injection channel 32 are simultaneously connected to an oil inlet pipe 33. In this embodiment, the first oil injection channel 31 and the second oil injection channel 32 are arranged in a V shape, and the intersection is simultaneously connected to the oil inlet pipe 33. The oil inlet pipe 33 is connected to the side of the stationary scroll disk 2, making the oil flow smoother, reducing the pipeline bends, and reducing the flow resistance. In a preferred setting, the included angle between the first oil injection channel 31 and the second oil injection channel 32 can be set as small as possible, which can further reduce the flow resistance of the oil. The diameters of the first oil injection channel 31 and the second oil injection channel 32 are the same.

[0020] The first oil injection channel 31 is connected with a first oil injection hole 311 and a second oil injection hole 312, and the second oil injection channel 32 is connected with a third oil injection hole 321 and a fourth oil injection hole 322. The arrangement order of the four oil injection holes is: along the spiral inward direction of the stationary scroll disk 2, they are the first oil injection hole 311, the second oil injection hole 312, the fourth oil injection hole 322, and the third oil injection hole 321 in sequence. And the openings of the third oil injection hole 321 and the fourth oil injection hole 322 are arranged on the inner side close to the profile line of the stationary scroll disk 2; the openings of the first oil injection hole 311 and the second oil injection hole 312 are both arranged on the outer side close to the profile line of the stationary scroll disk 2.

[0021] In this embodiment, the apertures of the first oil injection hole 311, the second oil injection hole 312, the third oil injection hole 321, and the fourth oil injection hole 322 are the same and smaller than the width of the moving scroll tooth 11. Preferably, the diameter of the hole is set to be 0.1 - 0.3 mm smaller than the thickness of the moving scroll tooth 11, so that when the moving scroll disk 1 translates, the moving scroll tooth 11 can completely cover the oil injection holes to avoid the occurrence of gas leakage between the first compression chamber 24 and the second compression chamber 25.

[0022] The distances between the first fuel injection hole 311 and the second fuel injection hole 312 and the outer wall of the stationary spiral teeth 23 of the stationary scroll disk 2 are greater than 0; the distances between the third fuel injection hole 321 and the fourth fuel injection hole 322 and the inner wall of the stationary spiral teeth are greater than 0, and preferably set that the distance from the edge of the hole to the outer wall of the stationary spiral teeth 23 is 0.1 - 0.3 mm, which can not only ensure that the holes can be completely covered during operation, but also ensure that the first fuel injection hole 311 and the fourth fuel injection hole 322 are opened in time during the intake stage, and the second fuel injection hole 312 and the third fuel injection hole 321 are closed in time before exhaust.

[0023] It should be noted that the first compression chamber 24 and the second compression chamber 25 are formed at the intake port 21. As the moving disk scroll moves translationally, while the volumes of the two compression chambers decrease, their positions also change in the rotational direction until they communicate with the exhaust port 22. This embodiment is based on the structure of a common symmetric scroll compressor. In one compression cycle, during the intake stage, when the first compression chamber 24 and the second compression chamber 25 are formed, the first compression chamber 24 and the second compression chamber 25 formed in the previous compression cycle move to the vicinity of the exhaust port 22 and have not yet communicated with the exhaust port 22. Therefore, there will be a situation where four compression chambers coexist. The formation of the first compression chamber 24 and the second compression chamber 25 described in this embodiment refers to a completely enclosed and independent chamber formed when the moving scroll disk 1 moves translationally relative to the stationary scroll disk 2 and does not communicate with the intake port 21 and the exhaust port 22. For the convenience of description, this embodiment divides one compression cycle into an intake stage, a compression stage, and an exhaust stage. In addition, in the design of some scroll compressors, the first compression chamber 24 and the second compression chamber 25 are not formed simultaneously, and there is a sequence in their formation. When the two compression chambers are formed successively, the positions of the first fuel injection hole 311 and the fourth fuel injection hole 322 can be slightly adjusted to achieve the effect of simultaneous fuel injection. However, generally, the time difference between the formation of the two compression chambers is extremely short, and whether to set sequential fuel injection does not affect the fuel injection effect. Therefore, in this embodiment, the first compression chamber 24 and the second compression chamber 25 are formed simultaneously for description.

[0024] During the intake stage, the overlapping areas of the first fuel injection hole 311 and the fourth fuel injection hole 322 with the moving spiral teeth 11 gradually decrease, and the opening degrees gradually increase. They respectively have a tendency to communicate with the first compression chamber 24 and the second compression chamber 25 and the communication area becomes larger. That is, when the first compression chamber 24 is formed, the first fuel injection hole 311 opens; when the second compression chamber 25 is formed, the fourth fuel injection hole 322 opens. It should be noted that in this stage, the opening of the first fuel injection hole 311 can be before the formation of the first compression chamber 24, or when the first fuel injection hole 311 has been partially opened, the first compression chamber 24 is formed. Similarly, the opening of the fourth fuel injection hole 322 can be before the formation of the second compression chamber 25, or when the fourth fuel injection hole 322 has been partially opened, the second compression chamber 25 is formed. The sequence of the first fuel injection hole 311 (or the fourth fuel injection hole 322) opening relative to the first compression chamber 24 (or the second compression chamber 25) depends on the actual design of the compressor scroll. During the exhaust stage, the second fuel injection hole 312 (or the third fuel injection hole 321) is in the process of gradually closing. That is, while the second fuel injection hole 312 (or the third fuel injection hole 321) is gradually closing, the first fuel injection hole 311 (or the fourth fuel injection hole 322) is gradually opening or has completed opening. Therefore, the first fuel injection passage 31 (or the second fuel injection passage 32) is always in a state of oil flow, continuously injecting fuel, to avoid the pulsation caused by the intermittent flow and stop of the oil.

[0025] During the exhaust stage, the overlapping areas of the second fuel injection hole 312 and the third fuel injection hole 321 with the moving spiral teeth 11 gradually increase, and the opening degrees gradually decrease. They respectively have a tendency to close with the first compression chamber 24 and the second compression chamber 25 and the closing area increases. That is, before the first compression chamber 24 is connected to the exhaust port 22, the second fuel injection hole 312 is completely closed; before the second compression chamber 25 is connected to the exhaust port 22, the third fuel injection hole 321 is completely closed.

[0026] In this embodiment, the specific fuel injection process of the first fuel injection hole 311, the second fuel injection hole 312, the third fuel injection hole 321, and the fourth fuel injection hole 322 in a compression cycle is as follows: 1. During the intake stage, as Figure 4-1 shown, when the first compression chamber 24 and the second compression chamber 25 are formed, the first fuel injection hole 311 and the fourth fuel injection hole 322 are partially covered or completely covered by the end face of the orbiting scroll 1 and are in a state of partial opening or about to open; as Figure 4-2 shown, the orbiting scroll 1 continues to translate, and the opening degrees of the first fuel injection hole 311 and the fourth fuel injection hole 322 increase to full opening.

[0027] 2. During the compression stage, as Figure 4-2 and Figure 4-3As shown, while the first fuel injection hole 311 and the fourth fuel injection hole 322 inject fuel into the first compression chamber 24 and the second compression chamber 25 respectively, the second fuel injection hole 312 and the third fuel injection hole 321 start to open until fully open, and also inject fuel into the first compression chamber 24 and the second compression chamber 25 respectively.

[0028] 3. During the exhaust stage, as Figure 4-4 shown, the second compression chamber 25 is first connected to the exhaust port 22, and the third fuel injection hole 321 is fully closed before the connection; then, as Figure 4-5 shown, the first compression chamber 24 is connected to the exhaust port 22, and the second fuel injection hole 312 is fully closed before the connection.

[0029] During the above process, as Figure 4-1 、 Figure 4-2 and Figure 4-4 、 Figure 4-5 the intake stage and the exhaust stage are overlapping processes. Combining Figure 5 shown is a schematic diagram of the first compression chamber 24 and the second compression chamber 25 of a 390° translational compression device from full closure to exhaust. Taking the first compression chamber 24 as an example: at 0°, it is fully closed, and the first fuel injection hole 311 connected to the first compression chamber 24 is partially open. Then, in sequence: the first fuel injection hole 311 is fully open, the second fuel injection hole 312 gradually starts to open until fully open, the first fuel injection hole 311 starts to close until fully closed, and finally at 390°, the first compression chamber 24 is connected to the exhaust port 22 and no longer injects fuel. Similarly, the second compression chamber 25 is closed and formed at 0°, and the fourth fuel injection hole 322 starts to open. Then, in sequence: the fourth fuel injection hole 322 is fully open, the third fuel injection hole 321 starts to open until fully open, the fourth fuel injection hole 322 starts to close until fully closed, and finally at about 340°, the second compression chamber 25 is connected to the exhaust port 22 and no longer injects fuel. During this process, the continuity of the oil flow reduces the pulsation of the oil circuit system; at the same time, the fuel injection process covers the entire process from intake to exhaust, greatly increasing the cooling efficiency.

[0030] In addition, it should be noted that due to the position settings of the four fuel injection holes, during the intake stage, even before the formation of the first compression chamber 24 (or the second compression chamber 25), the first fuel injection hole 311 (or the fourth fuel injection hole 322) has already started to inject fuel, with a small opening degree. And due to the V-shaped design of the first oil injection channel and the second oil injection channel, the first fuel injection hole 311 (or the fourth fuel injection hole 322) is far from the intake port, and the fuel injection duration before the chamber is fully closed is extremely short. Therefore, it will not preheat the gas and has no impact on the actual cooling efficiency.

[0031] The above embodiments are only used to illustrate the technical concept and features of the present invention. Their purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and should not be used to limit the protection scope of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to encompass all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A stationary scroll disk of a low-pulsation oil-injected scroll compressor, comprising a moving scroll disk and a stationary scroll disk, the stationary scroll disk includes an exhaust port and an oil injection mechanism, the moving scroll disk includes moving scroll teeth, and a first compression chamber and a second compression chamber are formed by the meshing of the stationary scroll disk and the moving scroll disk, and is characterized in that: The fuel injection mechanism includes a first fuel injection passage and a second fuel injection passage disposed inside the stationary scroll plate. The first fuel injection passage and the second fuel injection passage are both connected to the fuel inlet pipe. The first fuel injection passage is connected to a first fuel injection hole and a second fuel injection hole, and the openings are both disposed outside the scroll profile of the stationary scroll plate. The second fuel injection passage is connected to a third fuel injection hole and a fourth fuel injection hole, and the openings are disposed inside the scroll profile of the stationary scroll plate. During the intake stage, the overlapping areas of the first fuel injection hole and the fourth fuel injection hole with the moving scroll teeth gradually decrease, and the opening degrees gradually increase, respectively having a tendency to communicate with the first compression chamber and the second compression chamber and the communication area becoming larger. During the exhaust stage, the overlapping areas of the second fuel injection hole and the third fuel injection hole with the moving scroll teeth gradually increase, and the opening degrees gradually decrease, respectively having a tendency to close with the first compression chamber and the second compression chamber and the closing area increasing.

2. The static scroll disk of a low-pulsation fuel injection scroll compressor according to claim 1, characterized in that: The first fuel injection passage and the second fuel inlet passage are arranged in a V shape, and the intersection is simultaneously connected to the fuel inlet pipe.

3. The static scroll disk of a low-pulsation fuel injection scroll compressor according to claim 1, characterized in that: The fuel inlet pipe is connected to the side of the stationary scroll plate.

4. The static scroll disk of a low-pulsation fuel injection scroll compressor according to claim 1, characterized in that: The apertures of the first fuel injection hole, the second fuel injection hole, the third fuel injection hole, and the fourth fuel injection hole are all the same and smaller than the width of the moving scroll teeth.

5. A stationary scroll plate of a low-pulsation fuel injection scroll compressor according to claim 1, characterized in that: The distances between the first fuel injection hole and the second fuel injection hole and the outer wall of the stationary scroll teeth of the stationary scroll plate are greater than 0. The distances between the third fuel injection hole and the fourth fuel injection hole and the inner wall of the stationary scroll teeth are greater than 0.

6. A scroll compressor, applying the stationary scroll plate of the low-pulsation fuel injection scroll compressor according to any one of claims 1-5.

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