Oil separation structure of exhaust cover of scroll compressor

Abstract

The utility model discloses a scroll compressor exhaust cover oil separation structure which comprises an exhaust cover main body, an exhaust channel is arranged in the middle of the inner side of the exhaust cover main body, an exhaust small hole is formed in the exhaust cover main body above the exhaust channel, and an oil return cavity is formed in the exhaust cover main body at the bottom of the exhaust channel. The inner wall of the end, close to the oil return cavity, of the exhaust channel is a conical face, and an oil content insertion pipe is arranged on the upper portion of the interior of the exhaust channel. The four skewed slots are formed in the bottom of the oil separation insertion pipe, the slotting direction of the skewed slots is the same as the rotating direction of an oil-gas mixture instead of simply passing through the center line of the oil separation insertion pipe, due to the fact that the density of a refrigerant is small, part of the refrigerant can enter the oil separation insertion pipe in advance along with the skewed slots, and due to the fact that the density of refrigerant oil is large, the oil-gas mixture cannot enter the oil separation insertion pipe easily. And the oil can enter the oil return cavity along the wall surface of the oil return channel under the action of centrifugal force, gravity and surface tension, so that a better oil separation effect is realized.

Description

Technical Field

[0001] This utility model relates to the field of scroll compressor technology, and in particular to an oil separator structure for the exhaust cover of a scroll compressor. Background Technology

[0002] As one of the most critical components in the air conditioning system of new energy vehicles, the scroll compressor's oil return capability determines the oil content, friction loss between the scroll plates, and cooling capacity of the air conditioning system. During the operation of the scroll compressor, the refrigerant usually mixes with the refrigeration oil and enters the exhaust cover through the stationary plate exhaust port. Therefore, an oil separator needs to be installed in the exhaust cover to separate the two substances, allowing the refrigeration oil to flow back to the moving and stationary plates for lubrication, while the refrigerant is discharged from the exhaust cover.

[0003] Currently, centrifugal oil separator structures are the most widely used in scroll compressors. During operation, the mixture is discharged from the stationary plate exhaust port into the exhaust cover cavity, and then enters the exhaust channel tangentially through the exhaust orifice. In the annular flow channel between the exhaust channel and the oil separator tube, it rotates at high speed along the axis of the oil separator tube and moves towards the bottom. During this process, due to the difference in mass between the refrigerant and the refrigeration oil, the heavier refrigeration oil moves towards the bottom along the wall of the exhaust channel and enters the oil return chamber, while the lighter refrigerant enters the low-pressure area near the axis due to the weakening of centrifugal force during movement, and is thus carried out of the exhaust cover through the inside of the oil separator tube.

[0004] Although this structure is simple and has high oil separation efficiency, the following problems exist during use: 1. The position of the exhaust hole in the exhaust cover and the outer wall of the oil separator tube is not well matched, resulting in large flow resistance. During use, this will cause the top gray ring phenomenon, which will cause the exhaust pressure pulsation to increase sharply. Existing technology can improve the length-to-width ratio of the exhaust hole to bring the mixed fluid closer to the separator wall, thereby indirectly increasing the airflow rotation radius and improving the centrifugal force, thus improving the oil separation efficiency. However, changing the length-to-width ratio of the exhaust hole requires modification of the casting mold of the exhaust cover, which will scrap the original mold and result in high modification costs.

[0005] 2. Short-circuit flow is a secondary flow phenomenon, mainly manifested in the fact that particles do not enter the bottom as expected, but are discharged from the compressor with the gas. When the oil-gas mixture passes through the bottom of the oil separator tube, due to the short-circuit flow phenomenon, some of the refrigeration oil will be discharged from the compressor with the refrigerant, affecting the oil separator efficiency and increasing the oil content in the air conditioning system.

[0006] 3. The exhaust passage is usually machined into a cylindrical shape. With the loss of flow along the passage, the centrifugal force is weaker closer to the bottom of the passage, which causes some of the refrigeration oil to be sucked into the oil separator tube at the bottom and discharged from the compressor. Therefore, there is room for further improvement. Utility Model Content

[0007] The purpose of this utility model is to solve at least one of the technical problems existing in the prior art. By providing an oil separator structure for the exhaust cover of a scroll compressor, the above-mentioned problem is solved.

[0008] To achieve the above objectives, a scroll compressor exhaust cover oil separator structure is provided, including an exhaust cover body, an exhaust channel is provided in the middle of the inner side of the exhaust cover body, an exhaust hole is provided above the exhaust channel in the exhaust cover body, an oil return chamber is provided at the bottom of the exhaust channel in the exhaust cover body, the inner wall of the exhaust channel near the oil return chamber is a conical surface, and an oil separator insert is provided in the upper part of the exhaust channel.

[0009] The oil separation cannula includes a cannula body, an assembly surface is provided on the upper part of the cannula body, an oil separation surface is provided in the middle part of the cannula body, a Bezier curve transition surface is provided between the assembly surface and the oil separation surface, and multiple oblique grooves are opened on the bottom circumference of the cannula body.

[0010] According to the aforementioned oil separator structure for a scroll compressor exhaust cover, the exhaust passage is connected to the oil return chamber at the pointed end of the conical surface.

[0011] According to the aforementioned oil separation structure of the exhaust cover of a scroll compressor, the slotting direction of the plurality of inclined slots is the same as the rotation direction of the oil-gas mixture.

[0012] According to the aforementioned oil separator structure of the exhaust cover of a scroll compressor, the exhaust direction of the exhaust hole is tangent to the inner wall of the exhaust channel.

[0013] The above solution has at least one of the following beneficial effects:

[0014] 1. The bottom of the oil separator tube of this utility model is provided with four inclined slots, and the opening direction of the inclined slots is the same as the rotation direction of the oil-gas mixture, rather than simply passing through the center line of the oil separator tube. Since the refrigerant density is relatively small, some refrigerant will enter the oil separator tube in advance along the inclined slots, while the refrigeration oil, due to its higher density, will enter the oil return chamber along the wall of the oil return channel under the action of centrifugal force, gravity, and surface tension, thus achieving a better oil separation effect and enhancing the practicality of the device.

[0015] 2. In this utility model, the transition between the oil separator insertion tube assembly surface and the oil separator surface adopts a Bezier curve. Compared with the existing straight slope transition, a large curvature can be used first to form the transition of the assembly surface, and then a small curvature can be used to transition the large curvature surface to the oil separator surface. In this way, while maintaining a certain slope on the oil separator surface, the area of ​​fluid entering the oil separator channel is increased as much as possible, making the fluid transition at the inlet smoother. The fluid is turned by a large curvature through the smooth wall surface, so that the gas at the top moves downward along the surface, suppressing the occurrence of the top gray ring. At the same time, the change in the flow area greatly increases the internal tangential velocity, and the radial velocity and positive axial velocity near the internal wall surface will also increase, thereby improving the oil separator efficiency and enhancing the practicality of the device.

[0016] 3. The bottom of the oil return channel of this utility model is provided with a conical surface. By reducing the radial area of ​​the oil return channel, the centrifugal force that is reduced due to friction loss can be increased, so that the bottom of the oil return channel still maintains a large centrifugal force, which promotes oil-gas separation. At the same time, the conical surface at the bottom can be improved during the casting blank process. There is no need to change the mold. Only the shape of the oil return channel ejector pin needs to be changed, which makes the implementation cost lower.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0019] Figure 1 This is a front view of the oil separator structure of the exhaust cover of a scroll compressor according to the present invention.

[0020] Figure 2 for Figure 1 A schematic diagram of the AA-direction cross-section structure;

[0021] Figure 3 This is a front view of the oil separator insertion tube of this utility model.

[0022] Figure 4 This is a schematic diagram of the bottom structure of the oil separator tube of this utility model.

[0023] Legend:

[0024] 1. Exhaust cover body; 2. Exhaust passage; 3. Exhaust hole; 4. Oil return chamber; 5. Conical surface; 6. Oil separator pipe; 61. Pipe body; 62. Assembly surface; 63. Bézier curve transition surface; 64. Oil separator surface; 65. Inclined groove. Detailed Implementation

[0025] This section will describe in detail the specific embodiments of the present utility model. Preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present utility model. The drawings are all in a very simplified form and use non-precise proportions. They are only used to help to explain the embodiments of the present utility model in a convenient and clear way, and should not be construed as limiting the scope of protection of the present utility model.

[0026] Reference Figure 1-4 This utility model provides an oil separation structure for a scroll compressor exhaust cover, including an exhaust cover body 1. An exhaust channel 2 is provided in the middle of the inner side of the exhaust cover body 1. An exhaust hole 3 is provided above the exhaust channel 2 in the exhaust cover body 1. The exhaust direction of the exhaust hole 3 is tangent to the inner wall of the exhaust channel 2. An oil return chamber 4 is provided at the bottom of the exhaust channel 2 in the exhaust cover body 1. The inner wall of the exhaust channel 2 near the oil return chamber 4 is a conical surface 5. The tip of the exhaust channel 2 is connected to the oil return chamber 4. By reducing the radial area of ​​the oil return channel, the centrifugal force reduced due to friction loss can be increased, so that a large centrifugal force is still maintained at the bottom of the oil return channel, promoting oil-gas separation. At the same time, the conical surface at the bottom can be improved during the casting blank. It does not require changing the mold. Only the shape of the oil return channel ejector pin needs to be changed, which makes the implementation cost lower. An oil separation pipe 6 is provided inside the upper part of the exhaust channel 2. The exhaust channel 2 and the oil separation pipe 6 are combined to form an oil separation channel.

[0027] The oil separator tube 6 includes a tube body 61, an assembly surface 62 on the top of the tube body 61, an oil separator surface 64 in the middle of the tube body 61, and a Bezier curve transition surface 63 between the assembly surface 62 and the oil separator surface 64. Compared with the existing straight slope transition, a large curvature can be used first to form the transition of the assembly surface, and then a small curvature can be used to transition the large curvature surface to the oil separator surface. In this way, while maintaining a certain slope of the oil separator surface, the area of ​​fluid entering the oil separator channel is increased as much as possible, making the fluid transition at the inlet smoother. The fluid is turned 90° by the smooth wall surface, so that the top gas moves downward along the surface, suppressing the occurrence of top gray ring. At the same time, the change in the flow area greatly increases the internal tangential velocity, and the radial velocity and positive axial velocity near the internal wall surface will also increase, thereby improving the oil separator efficiency.

[0028] The bottom circumference of the insertion tube body 61 is provided with multiple inclined slots 65. The slots 65 are opened in the same direction as the rotation direction of the oil-gas mixture, and are not simply through the center line of the oil separator insertion tube. Because the refrigerant has a relatively low density, the refrigerant will enter the oil separator insertion tube in advance along the inclined slots 65. The refrigeration oil, due to its higher density, will enter the oil return chamber along the wall of the oil return channel under the action of centrifugal force, gravity and surface tension, thus achieving a better oil separation effect.

[0029] Working Principle: In operation, the assembly surface 62 and the oil separating surface 64 of the oil separator tube 6 adopt a Bezier curve transition. Compared with the existing straight slope transition, a large curvature can be used first to form the transition of the assembly surface, and then a small curvature can be used to transition the large curvature surface with the oil separating surface. In this way, while maintaining a certain slope of the oil separating surface, the area of ​​fluid entering the oil separating channel is increased as much as possible, making the fluid transition at the inlet smoother. The fluid is turned 90° by the smooth wall surface, so that the gas at the top moves downward along the surface, suppressing the occurrence of the top gray ring. At the same time, the change in the flow area greatly increases the internal tangential velocity, and the radial velocity and positive axial velocity near the internal wall surface will also increase, thereby improving the oil separation efficiency. Meanwhile, the inclined slot 65 opened at the bottom of the oil separator tube 6 allows the refrigerant to enter the interior of the oil separator tube 6 in advance with the inclined slot 65, achieving a better oil separation effect.

[0030] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. An oil separator structure for a scroll compressor exhaust cover, comprising an exhaust cover body (1), characterized in that: An exhaust channel (2) is provided in the middle of the inner side of the exhaust cover body (1). An exhaust hole (3) is provided above the exhaust channel (2) of the exhaust cover body (1). An oil return chamber (4) is provided at the bottom of the exhaust channel (2) of the exhaust cover body (1). The inner wall of the exhaust channel (2) near the oil return chamber (4) is a conical surface (5). An oil separator pipe (6) is provided above the interior of the exhaust channel (2). The oil separation cannula (6) includes a cannula body (61), an assembly surface (62) is provided on the upper part of the cannula body (61), an oil separation surface (64) is provided in the middle part of the cannula body (61), a Bezier curve transition surface (63) is provided between the assembly surface (62) and the oil separation surface (64), and multiple inclined grooves (65) are opened on the bottom circumference of the cannula body (61).

2. The oil separator structure for the exhaust cover of a scroll compressor according to claim 1, characterized in that, The exhaust channel (2) is connected to the oil return chamber (4) at the pointed end of the conical surface (5).

3. The oil separator structure for the exhaust cover of a scroll compressor according to claim 1, characterized in that, The slotting direction of the plurality of said inclined slots (65) is the same as the rotation direction of the oil-gas mixture.

4. The oil separator structure for the exhaust cover of a scroll compressor according to claim 1, characterized in that, The exhaust direction of the exhaust hole (3) is tangent to the inner wall of the exhaust channel (2).

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