Screw compressor and air conditioner

Abstract

The invention discloses a screw compressor and an air conditioner, relates to the field of compressors, and aims to improve the reliability of the screw compressor. The screw compressor comprises a compressor body, an oil separation barrel and a backpressure assembly. The compressor body comprises a suction end and an exhaust end; a first communicating flow channel is formed in the wall body of the compressor body, and one end of the first communicating flow channel communicates with the air suction end. The oil separation barrel is mounted at the exhaust end of the compressor body; the oil separation barrel is provided with a first exhaust port; a second communication flow channel is arranged in the wall body of the oil separation barrel; the second communicating flow channel is located at the downstream of the first communicating flow channel and communicates with the first communicating flow channel; the back pressure assembly is installed at the first exhaust port and comprises a movable sliding block. The backpressure assembly controls opening and closing of the first exhaust port by moving the sliding block. According to the technical scheme, the flowing length of gas at the air suction end outside the screw compressor is shortened, resonance and noise of an air conditioner can be greatly reduced, and the reliability of the air conditioner is improved.

Description

Technical Field

[0001] This invention relates to the field of compressors, and more specifically to a screw compressor and an air conditioner. Background Technology

[0002] Screw compressors typically use the reciprocating motion of a slide valve and an oil piston to achieve capacity or pressure ratio regulation. Capacity regulation and pressure ratio regulation are two regulation methods for screw compressors. In capacity regulation, the length of the mating section between the slide valve and the rotor is variable, while in pressure ratio regulation, the length of the mating section is constant, always at full load. The key to the reciprocating motion of the slide valve and oil piston lies in the compressor's operating conditions, specifically the pressure difference between the compressor's intake and exhaust. If the pressure difference between the intake and exhaust is too small, it is insufficient to overcome the resistance of the reciprocating motion, thus preventing loading and unloading.

[0003] In related technologies, central air conditioning systems often encounter cold start situations due to climate conditions and other reasons. During a cold start, because the system's condensing temperature is too low, the high-pressure side discharge pressure of the system cannot be increased after the compressor is turned on. The high and low pressure sides of the compressor cannot establish a sufficient high-low pressure difference, which will cause the compressor to fail to load. Insufficient oil supply to the compressor may cause serious damage to the compressor due to insufficient lubrication and cooling.

[0004] To address this issue, some air conditioners are equipped with a pressure maintaining valve. The function of this valve is to maintain pressure; it only opens when the pressure reaches the valve's opening pressure, allowing the screw compressor to discharge. The valve's opening depends on the difference between the pressure maintaining the discharge and the suction pressure, therefore it needs to be connected to the suction end of the screw compressor. After the screw compressor starts, the pressure maintaining valve allows the compressor to quickly establish a sufficient high-low pressure difference, ensuring smooth loading and unloading and preventing adverse effects from insufficient oil.

[0005] The inventors discovered that the prior art has at least the following problems: In existing air conditioners, the balance pipe connecting the pressure maintaining valve and the suction side of the screw compressor is too long. The excessively long balance pipe is prone to causing resonance in the air conditioner, which will increase the noise and affect the reliability of the air conditioner. Summary of the Invention

[0006] This invention proposes a screw compressor and an air conditioner to improve the reliability of the screw compressor.

[0007] This invention provides a screw compressor, comprising:

[0008] The compressor body includes an intake end and an exhaust end; a first connecting channel is provided inside the wall of the compressor body, and one end of the first connecting channel is connected to the intake end.

[0009] An oil separator is installed at the exhaust end of the compressor body; the oil separator is provided with a first exhaust port; a second connecting channel is provided inside the wall of the oil separator; the second connecting channel is located downstream of the first connecting channel and is connected to the other end of the first connecting channel;

[0010] A back pressure assembly is installed at the first exhaust port, the back pressure assembly including a slider movably disposed at the first exhaust port; the back pressure assembly controls the opening and closing of the first exhaust port by moving the slider;

[0011] The second connecting channel is configured to provide a first pressure to the back pressure assembly, and the gas inside the oil separator provides a second pressure to the back pressure assembly.

[0012] In some embodiments, the oil separator includes:

[0013] The cylinder is fixedly connected to the exhaust end of the compressor body;

[0014] A mounting base is located outside the cylinder body, and the two are integral or fixedly connected; the mounting base includes a mounting cavity and a first exhaust port; one end of the mounting cavity communicates with the interior of the cylinder body, and the other end of the mounting cavity is open; the first exhaust port penetrates the wall of the mounting base and communicates with it; the slider is installed inside the mounting cavity; and

[0015] An end cap is detachably mounted at the opening of the mounting cavity.

[0016] In some embodiments, the back pressure assembly further includes:

[0017] An elastic element is installed between the inner wall of the slider and the mounting base; and

[0018] A limiting member is installed on the inner wall of the mounting base and located at the end of the slider away from the elastic member. The limiting member is configured to restrict the position of the slider. When the slider is in a first extreme position, the slider blocks the first exhaust port and the slider is supported by the limiting member. When the slider is in a second extreme position, the slider is away from the first exhaust port and separate from the limiting member.

[0019] In some embodiments, the mounting base is further provided with a second exhaust port; the screw compressor further includes:

[0020] A switching valve is installed at the second exhaust port to control the opening and closing of the second exhaust port.

[0021] In some embodiments, the central axis of the first exhaust port and the central axis of the second exhaust port are parallel.

[0022] In some embodiments, the second exhaust port is located on the side of the first exhaust port near the central axis of the screw compressor.

[0023] In some embodiments, when the screw compressor is in a first operating condition, the first exhaust port is configured to be openable and the second exhaust port is configured to be closed;

[0024] When the screw compressor is in the second operating condition, the second exhaust port is configured to be openable, and the first exhaust port is configured to be closed.

[0025] In some embodiments, under the first operating condition, the pressure difference between the second pressure and the first pressure of the screw compressor is less than or equal to a; and / or,

[0026] Under the second operating condition, the pressure difference between the second pressure and the first pressure of the screw compressor is greater than a; wherein a is 0.2MPa to 0.3MPa.

[0027] In some embodiments, the screw compressor further includes:

[0028] A connecting pipe is located outside the compressor body and the oil separator tank; the connecting pipe includes an air inlet and an air outlet; the connecting pipe is located downstream of the second connecting channel and the air inlet of the connecting pipe is connected to the second connecting channel, and the air outlet of the connecting pipe is connected to the mounting cavity to provide a first pressure to the back pressure assembly.

[0029] In some embodiments, the second communication channel is directly connected to the mounting cavity.

[0030] In some embodiments, the first communicating channel is connected to the downstream end of the suction end of the compressor body.

[0031] In some embodiments, at least a portion of the first and second connecting channels are parallel to the axial direction of the screw compressor.

[0032] In some embodiments, the back pressure assembly is located at the top of the oil separator tank.

[0033] This invention also provides an air conditioner, including a screw compressor provided by any of the technical solutions of this invention.

[0034] The screw compressor provided by the above technical solution introduces the gas from the suction end of the screw compressor to the back pressure assembly by guiding the gas from the suction end through a first connecting flow channel inside the compressor body and a second connecting flow channel inside the oil separator tank. At this time, the gas from the suction end is already very close to the back pressure assembly, which can greatly shorten the length of the gas flowing outside the screw compressor, thereby greatly reducing the resonance and noise of the air conditioner and improving the reliability of the air conditioner. Attached Figure Description

[0035] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0036] Figure 1 This is a schematic diagram showing the first exhaust port of a screw compressor in a closed state, as provided in some embodiments of the present invention.

[0037] Figure 2 This is a schematic diagram showing the first exhaust port of a screw compressor in an open state, provided for some embodiments of the present invention.

[0038] Figure 3 This is a schematic diagram showing the first exhaust port of the screw compressor in a closed state, as provided in some other embodiments of the present invention.

[0039] Figure 4 This is a schematic diagram showing the first exhaust port of the screw compressor in an open state, provided for some other embodiments of the present invention.

[0040] Figure label:

[0041] 1. Compressor body; 2. Oil separator tank; 3. Back pressure assembly; 4. Connecting pipelines;

[0042] 11. Intake end; 12. Exhaust end; 13. First connecting flow channel;

[0043] 21. Second connecting channel; 22. First exhaust port; 23. Cylinder body; 24. Mounting base; 25. End cap; 26. Second exhaust port;

[0044] 31. Slider; 32. Elastic component; 33. Limiting component;

[0045] 41. Air inlet; 42. Air outlet. Detailed Implementation

[0046] The following is combined with Figures 1-4The technical solutions provided by this invention will be described in more detail below. The descriptions of exemplary embodiments are merely illustrative and are in no way intended to limit this disclosure or its application or use. This disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make this disclosure thorough and complete, and to fully express the scope of this disclosure to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0047] The terms “first,” “second,” and similar words used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as “including” or “contains” mean that the element preceding the word covers the element listed after the word, and do not exclude the possibility of covering other elements as well.

[0048] In this disclosure, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.

[0049] All terms used in this disclosure, including technical or scientific terms, have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0050] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment shall be considered part of the specification.

[0051] The dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Common structural elements or elements of the same kind are given the same reference numerals in the various drawings, and repeated descriptions of them are omitted where appropriate.

[0052] Figure 1 This is a schematic diagram showing the first exhaust port 22 of a screw compressor in a closed state, as provided in some embodiments of the present invention. Figure 2 This is a schematic diagram showing the first exhaust port 22 of a screw compressor in an open state, as provided in some embodiments of the present invention.

[0053] See Figure 1and Figure 2 This invention provides a screw compressor, including a compressor body 1, an oil separator 2, and a back pressure assembly 3. The compressor body 1 includes an intake end 11 and an exhaust end 12; a first connecting channel 13 is provided inside the wall of the compressor body 1, one end of which is connected to the intake end 11. The oil separator 2 is installed at the exhaust end 12 of the compressor body 1; the oil separator 2 has a first exhaust port 22; a second connecting channel 21 is provided inside the wall of the oil separator 2; the second connecting channel 21 is located downstream of the first connecting channel 13 and is connected to the other end of the first connecting channel 13. Figure 1 The blue solid line with arrows indicates the flow direction of the airflow in the first connecting channel 13 and the second connecting channel 21. The back pressure assembly 3 is installed at the first exhaust port 22 and includes a slider 31 movably disposed at the first exhaust port 22; the back pressure assembly 3 controls the opening and closing of the first exhaust port 22 by moving the slider 31. The second connecting channel 21 is configured to provide a first pressure Ps to the back pressure assembly 3, and the gas inside the oil separator 2 provides a second pressure Pm to the back pressure assembly 3.

[0054] The compressor body 1 is made of high-strength metal and serves to provide stable support and a mounting foundation for all compressor components. Inside the compressor body 1 are meshing male and female rotors. The compressor body 1 has an intake end 11 for drawing in outside air. The drawn-in air is compressed by the male and female rotors to obtain compressed gas. The compressed gas is then filtered through an oil separator 2 and discharged from the screw compressor.

[0055] The compressor's suction end 11 is a region from which external gas is introduced into the gap between the male and female rotors and compressed.

[0056] The compressor wall has a certain thickness, and the first connecting channel 13 is located inside the compressor wall, similar to being inside a "wall". The first connecting channel 13, located inside the compressor wall, can be a straight channel, a curved channel, or a zigzag channel. The shape of the first connecting channel 13 is preferably such that it guides the gas from the suction end 11 of the compressor body 1 to the back pressure assembly 3 with the shortest possible path. The first connecting channel 13 is connected to the suction end 11 of the compressor body 1, specifically, it can be connected to the downstream end of the suction end 11 of the compressor body 1. This shortens the length of the first connecting channel 13, reduces manufacturing difficulty, and reduces the path length of gas flow.

[0057] The function of the first connecting channel 13 is to apply a first pressure Ps to the back pressure assembly 3 at the suction end 11 of the compressor body 1. The first pressure Ps is also called the suction pressure. The gas in the oil separator 2 applies a second pressure Pm to the back pressure assembly 3. The second pressure Pm is also called the discharge pressure. In this way, the back pressure assembly 3 can implement a corresponding control strategy based on the pressure difference between the first pressure Ps and the second pressure Pm.

[0058] The oil separator tank 2 is airtightly connected to the compressor body 1 to prevent air leakage. The walls of the oil separator tank 2 are made of high-strength metal, and the tank is cylindrical. An internal filter is installed in the oil separator tank 2. The compressed oil-gas mixture is separated into gas and oil by the filter. The oil remains at the bottom of the oil separator tank 2, while the compressed gas is discharged through it. The oil separated in the oil separator tank 2 provides stable lubrication for the compressor body 1. When the compressor body 1 requires lubricating oil, the oil in the oil separator tank 2 can be promptly returned to the body through the oil return pipe, ensuring the normal operation of the compressor.

[0059] The back pressure assembly 3 is installed inside the oil separator tank 2. One end of the back pressure assembly 3 bears a first pressure Ps, and the other end bears a second pressure. It is controlled by the pressure difference between the first pressure Ps and the second pressure Pm of the screw compressor. When the pressure difference is sufficient to drive the slider 31 of the back pressure assembly 3 to move, the slider 31 avoids the first exhaust port 22, the first exhaust port 22 opens, and the gas inside the oil separator tank 2 is discharged to the outside of the screw compressor through the first exhaust port 22. When the pressure difference between the first pressure Ps and the second pressure Pm of the screw compressor is small and insufficient to open the back pressure assembly 3, the first exhaust port 22 is closed, and the gas inside the oil separator tank 2 cannot be discharged to the outside of the screw compressor through the first exhaust port 22. The back pressure assembly 3 can achieve gas suppression to regulate the pressure difference between the first pressure Ps and the second pressure Pm of the screw compressor.

[0060] In some embodiments, the back pressure assembly 3 is located on top of the oil separator tank 2 to cooperate with the first exhaust port 22 to achieve top exhaust of the screw compressor.

[0061] The above technical solution introduces the gas from the suction end 11 of the screw compressor to the back pressure assembly 3 by guiding the gas from the suction end 11 to the vicinity of the back pressure assembly 3 through the first connecting flow channel 13 inside the wall of the compressor body 1 and the second connecting flow channel 21 inside the wall of the oil separator tank 2. At this time, the gas from the suction end 11 is already very close to the back pressure assembly 3. Whether the connecting pipe 4 described later is set up, or the second connecting flow channel 21 is directly used to provide suction pressure to the back pressure assembly 3 (also referred to as the first pressure Ps in this article), the length of the gas from the suction end 11 flowing outside the screw compressor can be greatly shortened, which will also greatly reduce the resonance and noise of the air conditioner and improve the reliability of the air conditioner.

[0062] See also Figure 1 and Figure 2 In some embodiments, the oil separator 2 includes a cylinder 23, a mounting base 24, and an end cap 25. The cylinder 23 is fixedly connected to the exhaust end 12 of the compressor body 1. The mounting base 24 is located outside the cylinder 23, and the mounting base 24 and the cylinder 23 are integral or fixedly connected; the mounting base 24 protrudes from the cylinder 23, and in some embodiments, the mounting base 24 is installed on the top of the cylinder 23. The screw compressor has a top exhaust structure.

[0063] The mounting base 24 is, for example, cylindrical. The mounting base 24 is located outside the cylindrical body 23, and the mounting base 24 and the cylindrical body 23 are integrally formed or fixedly connected. The mounting base 24 includes a mounting cavity 20 and a first exhaust port 22. One end of the mounting cavity 20 communicates with the interior of the cylindrical body 23, and the other end of the mounting cavity 20 is open; the first exhaust port 22 penetrates the wall of the mounting base 24 and communicates with it; the back pressure assembly 3 is installed inside the mounting cavity 20.

[0064] The mounting cavity 20 of the mounting base 24 is open to facilitate the installation of the back pressure assembly 3. The end cap 25 seals the opening of the mounting cavity 20, making the installation and removal of the back pressure assembly 3 more convenient. After the end cap 25 is installed in place, the mounting cavity 20 and the interior of the cylinder 23 form a sealed cavity, and the gas in the oil separator 2 can only be discharged to the outside of the screw compressor through the first exhaust port 22 or the second exhaust port 26 described later.

[0065] See also Figure 1 and Figure 2 In some embodiments, the back pressure assembly 3 includes a slider 31, an elastic element 32, and a limiting element 33. The slider 31 is movably mounted within the mounting cavity 20. The elastic element 32 is mounted between the slider 31 and the inner wall of the mounting base 24. The elastic element 32 is, for example, a spring, which is in a compressed state. The limiting element 33 is mounted on the inner wall of the mounting base 24 and is located at the end of the slider 31 away from the elastic element 32. The limiting element 33 is configured to restrict the position of the slider 31; specifically, the limiting element 33 is, for example, a boss. One or more limiting elements 33 can be provided. If there is only one limiting element 33, the limiting element 33 can adopt a ring structure or a C-shaped structure to increase the contact area between the limiting element 33 and the slider 31, so that the slider 31 is stably supported. If there are multiple limiting elements 33, the multiple limiting elements 33 are evenly distributed along the circumference of the mounting cavity 20 to increase the force points of the slider 31 and the balance of force.

[0066] When slider 31 is at its first extreme position, slider 31 blocks the first exhaust port 22, and slider 31 is supported by limiting member 33. Figure 1The lower limit position is shown. The first limit position corresponds to the pressure difference between the second pressure Pm and the first pressure Ps being insufficient to overcome the elastic force of the elastic element 32. Under the action of the elastic element 32, the slider 31 is pressed against the limiting element 33.

[0067] When slider 31 is in the second extreme position, that is Figure 1 At the upper limit position shown, slider 31 is away from the first exhaust port 22, and slider 31 is separated from the limiting member 33. The second limit position corresponds to the pressure difference between the second pressure Pm and the first pressure Ps being sufficient to overcome the elastic force of the elastic member 32, and slider 31 is pushed upward.

[0068] The back pressure assembly 3 provided by the above structural scheme has a compact structure, contains a small number of components, and can effectively control whether the back pressure assembly 3 opens the first exhaust port 22 according to the first pressure Ps and the second pressure Pm of the screw compressor.

[0069] See also Figure 1 and Figure 2 In some embodiments, the mounting base 24 is also provided with a second exhaust port 26; the screw compressor also includes a switching valve (not shown), which is installed on the second exhaust port 26 to control the opening and closing of the second exhaust port 26. When the switching valve is in the open state, the gas in the oil separator 2 can be discharged to the outside of the screw compressor without resistance through the second exhaust port 26.

[0070] The opening and closing state of the second exhaust port 26 is not controlled by the back pressure component 3, but directly by the switching valve. The switching valve can determine whether to open the second exhaust port 26 based on the operating conditions. It should be noted that when the second exhaust port 26 is open, the first exhaust port 22 cannot be opened due to the presence of the back pressure component 3.

[0071] The above technical solution uses two exhaust ports to achieve exhaust, and the control strategies of the two exhaust ports are different. The first exhaust port 22 is used for exhaust in low pressure differential conditions, and the second exhaust port 26 is used for exhaust in other conditions, so that the overall energy efficiency of the screw compressor can be improved under various operating conditions.

[0072] In some embodiments, when the screw compressor is in a first operating condition, the first exhaust port 22 is configured to be openable, and the second exhaust port 26 is configured to be closed. The first operating condition is, for example, a low differential pressure condition, the applicability of which can be determined practically.

[0073] When the compressor pressure differential Pm-Ps is small, the system issues a command to close the second exhaust port 26 and open the first exhaust port 22. At this time, the second pressure Pm is too low to push open the slider 31. However, as time goes on, the second pressure Pm continues to rise in the oil separator 2 until the weight of the compressor pressure differential Pm-Ps spring and slider 31 is negligible and can flexibly push the slide valve and oil piston to move, at which point slider 31 can be pushed open to allow exhaust. It can be seen that exhaust under low pressure differential conditions solves the problem of compressor capacity or pressure regulation not working or being difficult to work, enabling smooth capacity or pressure regulation even under low pressure differential conditions.

[0074] For R22 or R134a refrigerants, the fully open pressure of the elastic element 32 is 0.7MPa to 0.75MPa. For other refrigerants, the pressure depends on the specific circumstances. Using a back-pressure structure to discharge from the first discharge port 22 results in some discharge losses due to overcoming spring force and compressor over-compression caused by the increased second pressure Pm, leading to lower compressor efficiency. Therefore, when the compressor pressure difference Pm-Ps is large, discharge can be directly achieved through the second discharge port 26, thus improving compressor efficiency.

[0075] In some embodiments, under the first operating condition, the pressure difference between the second pressure Pm and the first pressure Ps of the screw compressor is less than or equal to a. Wherein, a is 0.2 MPa to 0.3 MPa; specifically, a is, for example, 0.2 MPa, 0.25 MPa, 0.28 MPa, or 0.3 MPa. The pressure of the elastic element 32 can be set to 0.5 MPa to 0.7 MPa.

[0076] When the screw compressor is in the second operating condition, the second exhaust port 26 is configured to be openable, and the first exhaust port 22 is configured to be closed. The second operating condition specifically refers to any operating condition other than the first operating condition.

[0077] In some embodiments, under the second operating condition, the pressure difference between the second pressure Pm and the first pressure Ps of the screw compressor is greater than a. When the compressor pressure difference Pm-Ps is sufficiently large, the system issues a command to close the first discharge port 22 and open the second discharge port 26. The refrigerant is discharged through the second discharge port 26. No discharge loss occurs during this process, and the compressor efficiency is unaffected. Here, Pm is the second pressure Pm, and Ps is the first pressure Ps.

[0078] The first exhaust port 22 and the second exhaust port 26 are opened under different operating conditions, and they do not exhaust at the same time.

[0079] In some embodiments, the central axis of the first exhaust port 22 and the central axis of the second exhaust port 26 are parallel. The first exhaust port 22 and the second exhaust port 26 are close to each other and are both mounted on the mounting base 24. The exhaust directions of the first exhaust port 22 and the second exhaust port 26 are parallel. Regardless of which exhaust port is open, the exhaust direction of the screw compressor remains unchanged, and the exhaust position also remains essentially unchanged. In addition, the structure of the cylinder 23 of the oil separator 2 no longer requires additional exhaust ports, simplifying the structure of the cylinder 23 of the oil separator 2. The mounting base 24 is small in size, making it easy to manufacture the first exhaust port 22 and the second exhaust port 26.

[0080] Continue to see Figure 1 and Figure 2 In some embodiments, the second exhaust port 26 is located on the side of the first exhaust port 22 closer to the central axis of the screw compressor. This arrangement makes it easier to install the back pressure assembly 3.

[0081] Continue to see Figure 1 and Figure 2 In some embodiments, the screw compressor further includes a connecting pipe 4, located outside the compressor body 1 and the oil separator 2. The connecting pipe 4 includes an inlet 41 and an outlet 42; the connecting pipe 4 is located downstream of the second connecting channel 21, and its inlet 41 is connected to the second connecting channel 21, specifically through a quick-connect fitting. The outlet 42 of the connecting pipe 4 is connected to the mounting cavity 20, specifically through another quick-connect fitting, to provide a first pressure Ps to the back pressure assembly 3. Since the back pressure assembly 3 is located inside the oil separator 2, the gas inside the oil separator 2 provides a second pressure Pm to the back pressure assembly 3. When the pressure difference between the first pressure Ps and the second pressure Pm is sufficiently large, the pressure difference is sufficient to overcome the elastic force of the elastic element 32, and the slider 31 of the back pressure assembly 3 is moved. Otherwise, the slider 31 of the back pressure assembly 3 remains in its original position, i.e., supported by the limiting element 33.

[0082] In some embodiments, at least a portion of the first connecting channel 13 and the second connecting channel 21 are parallel to the axial direction of the screw compressor.

[0083] Screw compressors regulate capacity or pressure ratio through the reciprocating motion of a slide valve and an oil piston. When the screw compressor is in its first operating condition, i.e., a low differential pressure condition, the small pressure difference between Pm and Ps can cause the slide valve and oil piston to not move or move too slowly. Therefore, a back pressure assembly 3 is used to increase the compressor's second pressure Pm, increasing the Pm-Ps pressure difference to a design value ΔP that allows the slide valve and oil piston to move flexibly and discharge gas.

[0084] The screw compressor provided by the above technical solution introduces the first pressure Ps into the mounting cavity 20 mainly through the first connecting flow channel 13 and the second connecting flow channel 21. Compared with the solution of directly introducing the suction end 11 of the screw compressor into the discharge end 12 through the pipeline, the technical solution of the present invention requires a very short connecting pipeline 4, which reduces the noise and vibration caused by the external pipeline and reduces the cost of the compressor.

[0085] Figure 3 This is a schematic diagram showing the first exhaust port 22 of the screw compressor in a closed state, according to some other embodiments of the present invention. Figure 4 This is a schematic diagram showing the first exhaust port 22 of the screw compressor in an open state, according to some other embodiments of the present invention.

[0086] See Figure 3 and Figure 4 In other embodiments, the second connecting channel 21 is directly connected to the mounting cavity 20. The second connecting channel 21 includes multiple segments and is directly connected to the mounting cavity 20. This implementation eliminates the need for piping located outside the compressor body 1 and the oil separator 2 to introduce the first pressure Ps into the mounting cavity 20.

[0087] This invention also provides an air conditioner, including a screw compressor provided by any of the technical solutions of this invention.

[0088] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0089] In the description of this invention, each technical feature may be combined with other technical features where feasible.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A screw compressor, characterized in that: include: A compressor body (1) comprises an air intake end (11) and an air discharge end (12); a first communication channel (13) is provided inside a wall of the compressor body (1), and one end of the first communication channel (13) is connected to the air intake end (11); An oil separator barrel (2) is mounted on the exhaust end (12) of the compressor body (1); the oil separator barrel (2) is provided with a first exhaust port (22); a second communication channel (21) is provided inside the wall of the oil separator barrel (2); the second communication channel (21) is located downstream of the first communication channel (13) and is connected to the other end of the first communication channel (13); and A back pressure assembly (3) is installed at the first exhaust port (22), and the back pressure assembly (3) comprises a slider (31) movably arranged at the first exhaust port (22); the back pressure assembly (3) controls the opening and closing of the first exhaust port (22) by moving the slider (31); The second communicating flow channel (21) is configured to provide a first pressure (Ps) to the back pressure component (3), and the gas inside the oil separation barrel (2) provides a second pressure (Pm) to the back pressure component (3).

2. The screw compressor according to claim 1, characterized in that: The oil separation barrel (2) comprises: A cylinder (23) fixedly connected to the exhaust end (12) of the compressor body (1); The mounting seat (24) is located outside the barrel (23), and the two are integrated or fixedly connected; the mounting seat (24) comprises a mounting cavity (20) and the first exhaust port (22); one end of the mounting cavity (20) is communicated with the interior of the barrel (23), and the other end of the mounting cavity (20) is open; the first exhaust port (22) passes through the wall of the mounting seat (24) and is communicated with the first exhaust port (22); the slider (31) is installed inside the mounting cavity (20); and The end cover (25) is detachably mounted on the open portion of the mounting cavity (20).

3. The screw compressor according to claim 1 or 2, characterized in that: The back pressure assembly (3) further comprises: an elastic member (32) installed between the slider (31) and the inner wall of the mounting seat (24); and A limiting member (33) is mounted on the inner wall of the mounting seat (24) and is located at an end of the slider (31) away from the elastic member (32); the limiting member (33) is configured to limit the position of the slider (31); wherein, when the slider (31) is in a first extreme position, the slider (31) blocks the first exhaust port (22), and the slider (31) is supported by the limiting member (33); and when the slider (31) is in a second extreme position, the slider (31) is away from the first exhaust port (22), and the slider (31) is separated from the limiting member (33).

4. The screw compressor according to claim 3, characterized in that: The mounting seat (24) is also provided with a second exhaust port (26); the screw compressor further comprises: A switching valve is installed at the second exhaust port (26) to control the opening and closing of the second exhaust port (26).

5. The screw compressor according to claim 4, characterized in that: The central axis of the first exhaust port (22) and the central axis of the second exhaust port (26) are parallel.

6. The screw compressor according to claim 4, characterized in that: The second exhaust port (26) is located on a side of the first exhaust port (22) close to the central axis of the screw compressor.

7. The screw compressor according to claim 4, characterized in that: When the screw compressor is in a first operating state, the first exhaust port (22) is configured to be openable, and the second exhaust port (26) is configured to be closed; When the screw compressor is in the second operating state, the second exhaust port (26) is configured to be openable, and the first exhaust port (22) is configured to be closed.

8. The screw compressor according to claim 7, characterized in that: Under the first working condition, the pressure difference between the second pressure (Pm) and the first pressure (Ps) of the screw compressor is less than or equal to a; and / or, In the second working condition, the pressure difference between the second pressure (Pm) and the first pressure (Ps) of the screw compressor is greater than a; Among them, a is 0.2MPa~0.3MPa.

9. The screw compressor according to any one of claims 2, 4 to 8, characterized in that: Also includes: A connecting pipe (4) is located outside the compressor body (1) and the oil separator barrel (2); the connecting pipe (4) includes an air inlet (41) and an air outlet (42); the connecting pipe (4) is located downstream of the second connecting flow channel (21) and the air inlet (41) of the connecting pipe (4) is connected to the second connecting flow channel (21), and the air outlet (42) of the connecting pipe (4) is connected to the installation cavity (20) to provide the first pressure (Ps) to the back pressure assembly (3).

10. The screw compressor according to any one of claims 2, 4 to 8, characterized in that: The second communicating flow channel (21) is directly communicated with the mounting cavity (20).

11. The screw compressor according to any one of claims 1, 2, 4 to 8, characterized in that: The first communication channel (13) is in communication with a downstream end of the suction end (11) of the compressor body (1).

12. The screw compressor according to any one of claims 1, 2, 4 to 8, characterized in that: At least partial areas of the first communicating flow channel (13) and the second communicating flow channel (21) are parallel to the axial direction of the screw compressor.

13. The screw compressor according to any one of claims 1, 2, 4 to 8, characterized in that: The back pressure assembly (3) is located at the top of the oil separation barrel (2).

14. An air conditioner, characterized in that: include: The screw compressor according to any one of claims 1 to 13.

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