Motor lubricating system and compressor

Abstract

The invention relates to the technical field of compressors, and discloses a motor lubricating system comprising an oil tank comprising a first oil outlet end, a second oil outlet end and an oil return end; the motor lubricates the bearing; the first end of the main motor oil pump is connected with the first oil outlet end; the first end of the standby motor oil pump is connected with the second oil outlet end; the first end of the first oil inlet electromagnetic valve and the first end of the second oil inlet electromagnetic valve are connected with the second end of the main motor oil pump and the second end of the standby motor oil pump, and the second end of the first oil inlet electromagnetic valve is connected with the first end of the motor lubricating bearing; the second end of the second oil inlet electromagnetic valve is connected with the second end of the motor lubricating bearing; the first end of the first oil return electromagnetic valve is connected with the first end of the motor lubricating bearing, the second oil return electromagnetic valve is connected with the second end of the motor lubricating bearing, and the second ends of the first oil return electromagnetic valve and the second oil return electromagnetic valve are connected with the oil return end.

Description

Technical Field

[0001] The present invention relates to the technical field of compressors, and in particular to an electric motor lubrication system and a compressor. Background Art

[0002] Compressors mainly rely on large motors as the drive. Since high-power motors have high speeds and large loads, most of the motor bearings are selected as sliding bearings and are equipped with relevant lubrication stations to provide lubricating oil with stable and appropriate temperatures for lubrication. Since the compressor unit is an important part of the chemical process, the motor should not stop as much as possible to avoid production interruption.

[0003] Existing lubrication systems generally are equipped with a main pump and a standby pump. When the main pump is damaged, the standby pump will start to replace the main pump to ensure normal oil supply to the system. However, due to reasons such as pipeline oil leakage or blockage, even with the strategy of using the standby pump, the lubrication system may still suddenly supply oil abnormally or even stop supplying oil. At this time, the sensors of the lubrication system will shut down the main engine through an interlock method, leaving no time for on-site staff to make an emergency treatment plan. Currently, a common method to solve this problem is to use an elevated oil tank. Once the lubrication system fails to supply oil normally, the elevated oil tank relies on its own weight to maintain the stability of the oil supply pressure, so as to continue to operate for a certain period of time. In the petrochemical industry, it takes about 20 minutes to start another set of standby compressor units. Due to the long operation time and large required oil flow rate, a large-capacity elevated oil tank needs to be equipped, which increases the complexity and cost of the system, and the elevated oil tank is located at a high place, making maintenance inconvenient. Summary of the Invention

[0004] The present invention provides an electric motor lubrication system to solve the technical problems of increasing the complexity and cost of the system by equipping a large-capacity elevated oil tank, and the inconvenience of maintenance due to the elevated oil tank being located at a high place.

[0005] To solve the above technical problems, an embodiment of the present invention provides an electric motor lubrication system, including:

[0006] An oil tank, including a first oil outlet end, a second oil outlet end, and an oil return end;

[0007] An electric motor lubricating bearing;

[0008] A main electric motor oil pump, the first end of the main electric motor oil pump is connected to the first oil outlet end;

[0009] A standby electric motor oil pump, the first end of the standby electric motor oil pump is connected to the second oil outlet end;

[0010] The first inlet oil solenoid valve and the second inlet oil solenoid valve, the first ends of the first inlet oil solenoid valve and the second inlet oil solenoid valve are connected to the second end of the main motor oil pump and the second end of the standby motor oil pump, the second end of the first inlet oil solenoid valve is connected to the first end of the motor lubricating bearing, and the second end of the second inlet oil solenoid valve is connected to the second end of the motor lubricating bearing;

[0011] The first return oil solenoid valve and the second return oil solenoid valve, the first end of the first return oil solenoid valve is connected to the first end of the motor lubricating bearing, the second return oil solenoid valve is connected to the second end of the motor lubricating bearing, and the second ends of the first return oil solenoid valve and the second return oil solenoid valve are connected to the return oil end.

[0012] Further, the motor lubricating bearing includes a bearing, an oil slinger and an oil sump, the oil sump is located below the bearing, the oil slinger is installed on the bearing, and the lower part of the oil slinger contacts the lubricating oil in the oil sump.

[0013] Further, it further includes:

[0014] A flow sensor, the flow sensor is electrically connected to the main motor oil pump and the standby motor oil pump, one end of the flow sensor is connected to the second ends of the main motor oil pump and the standby motor oil pump, and the other end is connected to the first ends of the first inlet oil solenoid valve and the second inlet oil solenoid valve;

[0015] A pressure transmitter, the measuring end of the pressure transmitter is connected between the other end of the flow sensor and the first inlet oil solenoid valve and the second inlet oil solenoid valve.

[0016] Further, the number of the pressure transmitters is 3, and the 3 pressure transmitters are connected in series in sequence along the flow direction of the lubricating oil.

[0017] Further, it further includes a logic processing controller, the logic processing controller is electrically connected to the pressure transmitter, the first inlet oil solenoid valve, the second inlet oil solenoid valve, the first return oil solenoid valve and the second return oil solenoid valve, and the logic processing controller performs a two-out-of-three logical judgment on the alarm pressure value detected by the pressure transmitter to control the first inlet oil solenoid valve, the second inlet oil solenoid valve, the first return oil solenoid valve and the second return oil solenoid valve to close the valve.

[0018] Further, it further includes a water cooler, the water cooler is located between the main motor oil pump and the standby motor oil pump and the flow sensor, one end of the water cooler is connected to the second ends of the main motor oil pump and the standby motor oil pump, and the other end of the water cooler is connected to one end of the flow sensor.

[0019] Further, a throttle valve is further included. The throttle valve is located between the water cooler and the flow sensor. One end of the throttle valve is connected to the other end of the water cooler and one end of the flow sensor, and the other end of the throttle valve is connected to the oil return end.

[0020] Further, a relief valve is further included. The relief valve is located between the throttle valve and the flow sensor. One end of the relief valve is connected to the other end of the water cooler, one end of the flow sensor, and one end of the throttle valve, and the other end of the relief valve is connected to the oil return end.

[0021] Further, check valves are provided on the second ends of the main motor oil pump and the standby motor oil pump.

[0022] An embodiment of the present invention further provides a compressor, including the above-mentioned motor lubrication system.

[0023] Advantages of the embodiment of the present invention:

[0024] In the oil inlet pipeline of the motor lubricating bearing of the present invention, a first oil inlet solenoid valve and a second oil inlet solenoid valve are provided, and in the oil outlet pipeline, a first oil return solenoid valve and a second oil return solenoid valve are provided. The lubricating liquid in the fuel tank flows into the motor lubricating bearing from the first oil inlet solenoid valve and the second oil inlet solenoid valve, and flows out from the first oil return solenoid valve and the second oil return solenoid valve to achieve the forced lubrication function. If the main motor oil pump and the auxiliary motor oil pump fail and cannot meet the oil flow of the motor lubricating bearing, the valve ports of the first oil inlet solenoid valve, the second oil inlet solenoid valve, the first oil return solenoid valve, and the second oil return solenoid valve are closed, so that the motor lubricating bearing forms a stable oil cavity. Since the cooling efficiency will decrease during the internal operation of self-lubrication, resulting in a slow rise in temperature, after the motor lubricating bearing changes from forced lubrication to self-lubrication, it can maintain operation for 20 minutes, giving the staff time to start the standby compressor unit and ensuring the continuous operation of the production line. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of the motor lubrication system;

[0026] Among them, the reference numerals in the schematic drawings of the specification are as follows:

[0027] 1. Fuel tank, 2. Main motor oil pump, 3. Suction oil filter, 4. Standby motor oil pump, 5. Drain ball valve, 6. Check valve, 7. Ball valve, 8. Double-tube filter, 9. Water cooler, 10. First oil inlet solenoid valve, 11. Second oil inlet solenoid valve, 12. First oil return solenoid valve, 13. Second oil return solenoid valve, 14. Flow sensor, 15. Pressure transmitter, 16. Motor lubricating bearing, 17. Throttle valve, 18. Relief valve, 19. Liquid level sensor, 20. Heater, 21. Temperature sensor. Specific Embodiments

[0028] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0029] Please refer to Figure 1 , an embodiment of the present invention provides a compressor, and the motor lubrication system can be applied to the compressor. Specifically, the motor lubrication system includes:

[0030] An oil tank 1, including a first oil outlet end, a second oil outlet end, and an oil return end;

[0031] A motor lubrication bearing 16;

[0032] A main motor oil pump 2, the first end of the main motor oil pump 2 is connected to the first oil outlet end;

[0033] A standby motor oil pump 4, the first end of the standby motor oil pump 4 is connected to the second oil outlet end;

[0034] A first inlet oil solenoid valve 10 and a second inlet oil solenoid valve 11, the first ends of the first inlet oil solenoid valve 10 and the second inlet oil solenoid valve 11 are connected to the second end of the main motor oil pump 2 and are also connected to the second end of the standby motor oil pump 4. The second end of the first inlet oil solenoid valve 10 is connected to the first end of the motor lubrication bearing 16, and the second end of the second inlet oil solenoid valve 11 is connected to the second end of the motor lubrication bearing 16;

[0035] A first oil return solenoid valve 12 and a second oil return solenoid valve 13, the first end of the first oil return solenoid valve 12 is connected to the first end of the motor lubrication bearing 16, the second oil return solenoid valve 13 is connected to the second end of the motor lubrication bearing 16, and the second ends of the first oil return solenoid valve 12 and the second oil return solenoid valve 13 are connected to the oil return end.

[0036] Specifically, the main motor oil pump 2 and the standby motor oil pump 4 are used to output lubricating oil with a certain pressure and flow rate to the motor lubrication bearing 16.

[0037] Specifically, the motor lubrication bearing 16 is a hydrodynamic bearing. The main function of forced lubrication is to provide a stable flow of lubricating oil, enabling it to带走 the heat of the bearing and keep the lubricating oil at a suitable temperature and form a stable oil film. However, too high an oil temperature will cause the viscosity of the oil to decrease and a stable oil film cannot be generated.

[0038] Before starting the main motor oil pump 2 and the standby motor oil pump 4 in this embodiment, it is necessary to first detect whether the amount of lubricating oil in the oil tank 1 is sufficient and whether the oil temperature is suitable. Specifically, a liquid level sensor 19, a temperature sensor 21, and a heater 20 can be provided on the oil tank 1. The liquid level sensor 19 is used to monitor the liquid level height of the lubricating oil in the oil tank 1, that is, the oil amount. When it is lower than the liquid level preset threshold, preferably, the liquid level preset threshold can be 100 mm, a warning can occur to remind the staff to refuel until the liquid level reaches 240 mm. The temperature sensor 21 is used to monitor the temperature of the lubricating oil in the oil tank 1. When it is lower than the temperature preset threshold, preferably, the minimum temperature preset threshold can be 5 °C, the heater 20 is started to heat the lubricating oil, and the temperature of the lubricating oil is continuously monitored. When the oil temperature reaches 10 °C, the heating is stopped.

[0039] In this embodiment, sufficient oil amount means that the liquid level is greater than 100 mm, and suitable oil temperature means that the oil temperature is greater than 5 °C. Under the condition of meeting these two conditions, the system automatically detects whether there is a fault signal in the main motor oil pump 2 and the standby motor oil pump 4. If not, the main motor oil pump 2 is automatically started. Only when the main motor oil pump 2 fails, resulting in insufficient oil supply, will the standby motor oil pump 4 be started to ensure that enough lubricating oil enters the motor lubricating bearing 16.

[0040] An oil suction filter 3 is provided at the first ends of the main motor oil pump 2 and the standby motor oil pump 4 to filter the lubricating oil flowing out of the oil tank 1, which belongs to coarse filtration, and then flows into the main motor oil pump 2 and the standby motor oil pump 4. Drain ball valves 5 are respectively provided at the second ends of the main motor oil pump 2 and the standby motor oil pump 4 for pumping out the lubricating oil in the oil tank 1. Check valves 6 are respectively provided at the second ends of the main motor oil pump 2 and the standby motor oil pump 4 to prevent the lubricating oil from flowing back into the oil tank 1. Specifically, the drain ball valve 5 is located between the check valve 6 and the main motor oil pump 2 or between the check valve 6 and the standby motor oil pump 4.

[0041] When the main motor oil pump 2 and the standby motor oil pump 4 fail, in order to facilitate the replacement of components during maintenance, a ball valve 7 is connected to the end of the check valve 6 far from the drain ball valve 5 for shutting off the circuit.

[0042] A duplex filter 8 is also provided between the ball valve 7 and the water cooler 9 for filtering the particulate contaminants in the lubricating oil, which belongs to fine filtration. The lubricating oil after fine filtration is输送至电机润滑轴承16进行润滑,延长电机润滑轴承16的使用寿命。

[0043] It should be noted that there is an unclear expression "输送至电机润滑轴承16进行润滑,延长电机润滑轴承16的使用寿命。" in the original text. I have translated it as best as possible, but it may need to be adjusted according to the correct context.Specifically, the motor lubricating bearing 16 includes a bearing, an oil slinger, and an oil sump. The oil sump is located below the bearing. The oil slinger is installed on the bearing, and the lower part of the oil slinger contacts the lubricating oil in the oil sump. When the motor operates, the rotation of the bearing drives the oil slinger to rotate. The lower part of the oil slinger dips the lubricating oil from the oil sump. As the oil slinger continuously rotates, the lubricating oil is thrown onto the raceway and rolling elements of the bearing by the centrifugal force of the oil slinger, achieving lubrication.

[0044] When the main motor oil pump 2 and / or the standby motor oil pump 4 operates, the lubricating oil flows into the motor lubricating bearing 16 from the first inlet solenoid valve 10 and the second inlet solenoid valve 11, and flows out from the first return solenoid valve 12 and the second return solenoid valve 13. The lubrication method of the motor lubricating bearing 16 is forced lubrication.

[0045] Specifically, the first inlet solenoid valve 10, the second inlet solenoid valve 11, the first return solenoid valve 12, and the second return solenoid valve 13 can be normally open valves. When the main motor oil pump 2 and the standby motor oil pump 4 fail and the oil flow rate into the motor lubricating bearing 16 is insufficient, to avoid bearing heating and shaft burning, the first inlet solenoid valve 10, the second inlet solenoid valve 11, the first return solenoid valve 12, and the second return solenoid valve 13 are controlled to be energized. After being energized, the four solenoid valves close, blocking the inlet oil path and the outlet oil path, forming a stable oil cavity, and changing the motor lubricating bearing 16 from forced lubrication to self-lubrication. Since the cooling efficiency during the internal operation of self-lubrication will decrease, resulting in a slow rise in temperature, it is known from the inventor's experiments that the motor lubricating bearing 16 can maintain operation for 20 minutes, giving the staff time to activate the standby compressor unit and ensuring the continuous operation of the production line without interruption of production.

[0046] The inlet pipeline of the motor lubricating bearing 16 of the present invention is provided with the first inlet solenoid valve 10 and the second inlet solenoid valve 11, and the outlet pipeline is provided with the first return solenoid valve 12 and the second return solenoid valve 13. The lubricating liquid in the fuel tank 1 flows into the motor lubricating bearing 16 from the first inlet solenoid valve 10 and the second inlet solenoid valve 11, and flows out from the first return solenoid valve 12 and the second return solenoid valve 13, realizing the function of forced lubrication. If the main motor oil pump 2 and the standby motor oil pump 4 fail and cannot meet the oil flow rate of the motor lubricating bearing 16, the valve ports of the first inlet solenoid valve 10, the second inlet solenoid valve 11, the first return solenoid valve 12, and the second return solenoid valve 13 are closed, causing the motor lubricating bearing 16 to form a stable oil cavity. Since the cooling efficiency during the internal operation of self-lubrication will decrease, resulting in a slow rise in temperature, after the motor lubricating bearing 16 is changed from forced lubrication to self-lubrication, it can maintain operation for 20 minutes, giving the staff time to activate the standby compressor unit and ensuring the continuous operation of the production line.

[0047] Specifically, it further includes a throttle valve 17. The throttle valve 17 is located between the water cooler 9 and the flow sensor 14. One end of the throttle valve 17 is connected to the other end of the water cooler 9 and one end of the flow sensor 14, and the other end of the throttle valve 17 is connected to the oil return end. The throttle valve 17 is used to return the excess oil fluid output by the main motor oil pump 2 and / or the standby motor oil pump 4 to the fuel tank 1, preventing excessive flow from being input to the bearing.

[0048] Specifically, the motor lubrication system further includes:

[0049] A flow sensor 14. The flow sensor 14 is electrically connected to the main motor oil pump 2 and the standby motor oil pump 4. One end of the flow sensor 14 is connected to the second ends of the main motor oil pump 2 and the standby motor oil pump 4, and the other end is connected to the first ends of the first oil inlet solenoid valve 10 and the second oil inlet solenoid valve 11.

[0050] A pressure transmitter 15. The measuring end of the pressure transmitter 15 is connected between the other end of the flow sensor 14 and the first oil inlet solenoid valve 10 and the second oil inlet solenoid valve 11.

[0051] The flow sensor 14 is used to monitor the oil flow rate input to the motor lubrication bearing 16. If there is a blockage in the pipeline at the back end, due to the function of the throttle valve 17, the lubricating oil can be returned to the fuel tank 1, so that the pressure in the pipeline will not jump too high, but the oil flow rate will decrease. The flow sensor 14 issues an alarm and activates the standby motor oil pump 4 to prevent the output oil flow rate from being too small for a long time, resulting in bearing overheating and shaft burning.

[0052] Specifically, the number of pressure transmitters 15 is 3, and the 3 pressure transmitters 15 are connected in series in sequence along the flow direction of the lubricating oil.

[0053] Specifically, it further includes a logic processing controller (not shown in the figure). The logic processing controller is electrically connected to the pressure transmitter 15, the first oil inlet solenoid valve 10, the second oil inlet solenoid valve 11, the first oil return solenoid valve 12, and the second oil return solenoid valve 13. The logic processing controller performs a two-out-of-three logical judgment on the alarm pressure value detected by the pressure transmitter 15 and controls the first oil inlet solenoid valve 10, the second oil inlet solenoid valve 11, the first oil return solenoid valve 12, and the second oil return solenoid valve 13 to close the valves.

[0054] The logic processing controller is used to monitor the pressure value of the pressure transmitter 15. When two out of the three pressure values are higher than the first threshold or lower than the second threshold and the first threshold is greater than the second threshold, an alarm is issued. Here, the first threshold and the second threshold are the alarm pressure values. After triggering the alarm, an operation instruction to close the valve ports is sent to the first oil inlet solenoid valve 10, the second oil inlet solenoid valve 11, the first oil return solenoid valve 12, and the second oil return solenoid valve 13, that is, the first oil inlet solenoid valve 10, the second oil inlet solenoid valve 11, the first oil return solenoid valve 12, and the second oil return solenoid valve 13 are energized. In a specific embodiment, when the pipeline between the main motor oil pump 2 and the standby motor oil pump 4 to the motor lubricating bearing 16 bursts or leaks, the flow rate monitored by the flow sensor 14 will be normal, and the pressure transmitter 15 can see that the pressure is too low, so as to check whether there is a leak causing the low pressure, preventing the output flow rate from being too small for a long time, resulting in bearing heating and shaft burning.

[0055] The flow sensor 14 is used to monitor the flow rate of the pipeline. When the main motor oil pump 2 is enabled, if the flow rate is small, the standby motor oil pump 4 is enabled. The three pressure transmitters 15 adopt a two-out-of-three control strategy to control the closing of the four solenoid valves, so that the motor lubricating bearing 16 switches to self-lubrication, replacing the emergency operation of the elevated oil tank. The principle of the motor lubrication system in this embodiment is simpler.

[0056] Specifically, it further includes an overflow valve 18. The overflow valve 18 is located between the throttle valve 17 and the flow sensor 14. One end of the overflow valve 18 is connected to the other end of the water cooler 9, one end of the flow sensor 14, and one end of the throttle valve 17, and the other end of the overflow valve 18 is connected to the oil return end. The overflow valve 18 is used to limit the maximum pressure of the output lubricating oil pump. Since the motor bearing will leak oil when the pipeline pressure is too high, when the pressure exceeds the set value of the overflow valve 18, it will open to discharge the excess flow rate and control the pressure below the set value.

[0057] Specifically, it further includes a water cooler 9. The water cooler 9 is located between the main motor oil pump 2 and the standby motor oil pump 4 and the flow sensor 14. One end of the water cooler 9 is connected to the second ends of the main motor oil pump 2 and the standby motor oil pump 4, and the other end of the water cooler 9 is connected to one end of the flow sensor 14. The water cooler 9 is used to reduce the oil temperature to a suitable temperature. Preferably, the temperature after cooling by the water cooler 9 is less than 45 °C.

[0058] The above specific embodiments have further detailed the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. In particular, it is pointed out that for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A motor lubrication system, characterized in that: include: An oil tank, comprising a first oil outlet end, a second oil outlet end and an oil return end; Lubricate motor bearings; A main motor oil pump, wherein a first end of the main motor oil pump is connected to the first oil outlet end; A standby motor oil pump, wherein a first end of the standby motor oil pump is connected to the second oil outlet end; a first oil inlet solenoid valve and a second oil inlet solenoid valve, wherein the first ends of the first oil inlet solenoid valve and the second oil inlet solenoid valve are connected to the second end of the main motor oil pump and to the second end of the standby motor oil pump, the second end of the first oil inlet solenoid valve is connected to the first end of the motor lubrication bearing, and the second end of the second oil inlet solenoid valve is connected to the second end of the motor lubrication bearing; A first oil return solenoid valve and a second oil return solenoid valve, wherein the first end of the first oil return solenoid valve is connected to the first end of the motor lubrication bearing, the second oil return solenoid valve is connected to the second end of the motor lubrication bearing, and the second ends of the first oil return solenoid valve and the second oil return solenoid valve are connected to the oil return end.

2. The motor lubrication system according to claim 1, characterized in that: The motor lubrication bearing comprises a bearing, an oil slinger and an oil pool, wherein the oil pool is located below the bearing, the oil slinger is mounted on the bearing, and the lower part of the oil slinger is in contact with the lubricating oil in the oil pool.

3. The motor lubrication system according to claim 1, characterized in that: Also includes: A flow sensor, wherein the flow sensor is electrically connected to the main motor oil pump and the standby motor oil pump, one end of the flow sensor is connected to the second end of the main motor oil pump and the standby motor oil pump, and the other end of the flow sensor is connected to the first end of the first oil inlet solenoid valve and the second oil inlet solenoid valve; A pressure transmitter, wherein a measuring end of the pressure transmitter is connected between the other end of the flow sensor and the first oil inlet solenoid valve and the second oil inlet solenoid valve.

4. The motor lubrication system according to claim 3, characterized in that: The number of the pressure transmitters is 3, and the 3 pressure transmitters are connected in series in sequence along the flow direction of the lubricating oil.

5. The motor lubrication system according to claim 4, characterized in that: It also includes a logic processing controller, which is electrically connected to the pressure transmitter, the first oil inlet solenoid valve, the second oil inlet solenoid valve, the first oil return solenoid valve and the second oil return solenoid valve. The logic processing controller performs a two-out-of-three logic judgment on the alarm pressure values ​​detected by the pressure transmitter, and controls the first oil inlet solenoid valve, the second oil inlet solenoid valve, the first oil return solenoid valve and the second oil return solenoid valve to close.

6. The motor lubrication system according to claim 3, characterized in that: It also includes a water cooler, which is located between the main motor oil pump, the standby motor oil pump and the flow sensor, one end of the water cooler is connected to the second end of the main motor oil pump and the standby motor oil pump, and the other end of the water cooler is connected to one end of the flow sensor.

7. The motor lubrication system according to claim 6, characterized in that: It also includes a throttle valve, which is located between the water cooler and the flow sensor, one end of the throttle valve is connected to the other end of the water cooler and one end of the flow sensor, and the other end of the throttle valve is connected to the oil return end.

8. The motor lubrication system according to claim 7, characterized in that: It also includes an overflow valve, which is located between the throttle valve and the flow sensor. One end of the overflow valve is connected to the other end of the water cooler, one end of the flow sensor and one end of the throttle valve, and the other end of the overflow valve is connected to the oil return end.

9. The motor lubrication system according to claim 1, characterized in that: One-way valves are provided on the second ends of the main motor oil pump and the standby motor oil pump.

10. A compressor, characterized in that: The motor lubrication system comprises the motor lubrication system according to any one of claims 1 to 9.

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