Liquid level control system and compressor

Abstract

The invention provides a liquid level control system and a compressor. The liquid level control system comprises a floating ball control unit, an electric heater and a frequency converter. The floating ball control unit is electrically connected with the electric heater or the frequency converter, the electric heater is used for increasing the temperature of an oil pool in the compressor shell, and the frequency converter is used for adjusting the rotating speed of the motor. The floating ball control unit is configured to be switched on when the internal liquid level of the compressor reaches a preset position to drive the electric heater or the frequency converter to operate, so that the internal liquid level of the compressor is always in a safe range; wherein the electric heater is mounted in the compressor shell through the mounting device. According to the configuration, a technician can control the internal liquid level of the compressor by arranging different numbers of floating ball control units to be connected with different functional devices respectively, so that the internal liquid level of the compressor is always in a safe range, poor lubrication of the compressor caused by too high or too low internal liquid level is avoided, and the service life of the compressor is prolonged. And thus, failure is avoided.

Description

Technical Field

[0001] The invention relates to the field of compressor manufacturing, in particular to a liquid level control system and a compressor. Background Art

[0002] When the air-conditioning refrigeration system is in operation, the compressor is prone to poor lubrication due to lack of oil, refrigerant migration during shutdown in a low-temperature environment, etc., which in turn causes problems such as compressor failure.

[0003] When the compressor runs at a low frequency, the gas flow rate is not high, so it cannot bring all the lubricating oil retained in the system pipeline back to the compressor. After long-term operation, more and more lubricating oil will be retained in the system pipeline, and the compressor oil level will be lower than the operating safety line. At this time, it is necessary to switch the compressor operation mode, increase the compressor operating frequency, and then increase the refrigerant flow rate to bring the retained lubricating oil back to the compressor from the system pipeline.

[0004] When the air-conditioning system is shut down for a long time in a low-temperature environment, the refrigerant in the system will accumulate in the compressor on the outdoor side. The large influx of refrigerant will cause the liquid level in the compressor to rise, dilute the lubricating oil, and cause the viscosity of the lubricating oil to decrease, resulting in poor lubrication when the compressor is started, and aggravated failure of the compressor shaft diaphragm. At this time, an electric heating tape is generally wrapped around the outside of the compressor casing, and it starts working when the temperature is lower than the preset temperature. The compressor should be preheated for more than six hours in advance before starting the compressor. Summary of the invention

[0005] The object of the present invention is to provide a liquid level control system and a compressor to solve the problem of poor lubrication and subsequent failure of the compressor caused by reasons such as low-frequency operation of the compressor or refrigerant migration when the compressor is shut down in a low-temperature environment.

[0006] In order to achieve the above object, the present invention provides a liquid level control system, including: a float control unit, an electric heater, and a frequency converter;

[0007] The float control unit is electrically connected to the electric heater or the frequency converter, the electric heater is used to increase the temperature of the oil pool inside the compressor housing, and the frequency converter is used to adjust the motor speed;

[0008] The float control unit is configured to: conduct when the internal liquid level of the compressor reaches a preset position, drive the electric heater or the inverter to operate, so that the internal liquid level of the compressor is always within a safe range;

[0009] Wherein, the liquid level control system further comprises a mounting device, and the electric heater is mounted inside the compressor housing through the mounting device.

[0010] Optionally, the mounting device includes a snap-fit ​​mechanism, and the electric heater is snap-fitted and connected to the snap-fit ​​mechanism.

[0011] Optionally, the engaging mechanism comprises a receiving groove and a plurality of guiding grooves, the receiving groove and the guiding groove are both located on the inner wall of the compressor housing, the receiving groove is arranged along the circumferential direction of the compressor housing, the guiding groove is arranged along the axial direction of the compressor housing, a plurality of guiding grooves are arranged at intervals along the circumferential direction of the compressor housing, and one end of the guiding groove is connected to the receiving groove;

[0012] A plurality of protrusions matching the guide grooves are provided on the outer circumference of the electric heater. The protrusions are passed through the guide grooves one by one, and after passing through the accommodating grooves from the guide grooves, they are rotated by a preset angle along the circumference of the compressor housing to achieve the connection between the electric heater and the compressor housing.

[0013] Optionally, the locking mechanism includes a plurality of protrusions, which extend toward the interior of the compressor housing and are welded to the inner wall of the compressor housing. The plurality of protrusions are arranged at intervals along the circumference of the compressor housing, and the electric heater is locked and connected to the protrusions.

[0014] Optionally, the electric heater is encapsulated in a metal ring tube or a plastic ring tube.

[0015] Optionally, the liquid level control system includes a first float control unit and a second float control unit;

[0016] The first float control unit is electrically connected to the electric heater, and the first float control unit is configured to: turn on when the internal liquid level of the compressor reaches a first preset position, drive the electric heater to operate, so as to increase the temperature of the oil pool inside the compressor housing;

[0017] The second float control unit is electrically connected to the frequency converter, and is configured to be turned on when the internal liquid level of the compressor reaches a second preset position, and drive the frequency converter to operate so as to adjust the motor speed.

[0018] Optionally, the first preset position includes: 0mm to 40mm from the lower core surface of the stator of the compressor or 0mm to 40mm from the upper core surface of the stator of the compressor; the second preset position includes: 0mm to 10mm above the dust collecting ring of the compressor.

[0019] Optionally, the liquid level control system further includes a third float control unit and an alarm unit;

[0020] The third float control unit is electrically connected to the alarm unit, and the third float control unit is configured to be turned on when the internal liquid level of the compressor reaches a third preset position, and drive the alarm unit to send an alarm signal.

[0021] Optionally, the liquid level control system also includes a relay, and the float control unit is electrically connected to the electric heater or the frequency converter through the relay, and the relay is configured to send a heating instruction to the electric heater or a speed regulation instruction to the frequency converter when the float control unit is turned on.

[0022] In order to achieve the above object, the present invention further provides a compressor, comprising a compressor housing, an oil pool and the liquid level control system as described above;

[0023] The oil pool is arranged inside the compressor housing, and the float control unit is arranged inside the oil pool. The float control unit drives the electric heater or the inverter to operate based on the rise and fall of the liquid level in the oil pool, so that the liquid level in the oil pool is always within a safe range.

[0024] In summary, in the liquid level control system and the compressor proposed in the present invention, the liquid level control system includes: a float control unit, an electric heater, and a frequency converter; the float control unit is electrically connected to the electric heater or the frequency converter, the electric heater is used to increase the oil pool temperature inside the compressor housing, and the frequency converter is used to adjust the motor speed; the float control unit is configured to: be turned on when the internal liquid level of the compressor reaches a preset position, drive the electric heater or the frequency converter to operate, so that the internal liquid level of the compressor is always within a safe range; wherein, the liquid level control system also includes an installation device, and the electric heater is installed inside the compressor housing through the installation device.

[0025] With such configuration, technicians can set different numbers of float control units and connect them to different functional devices to achieve control of the internal liquid level of the compressor. For example, a float control unit is set at the upper limit and the lower limit of the safety range respectively. When the internal liquid level exceeds the upper limit of the safety range, the electric heater is driven to heat it; when the internal liquid level exceeds the lower limit of the safety range, the inverter is driven to increase the operating frequency of the compressor, so as to ensure that the internal liquid level of the compressor is always within the safe range, avoiding the situation where the internal liquid level is too high or too low, causing poor lubrication of the compressor and thus failure; in addition, the electric heater is set inside the compressor casing to directly heat the oil pool. Compared with the solution of setting it outside the compressor casing and transferring heat through the compressor casing, the heat transfer steps are reduced, the heat loss during the transfer process is reduced, and the working efficiency of the liquid level control system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of a first liquid level control system proposed in an embodiment of the present invention;

[0027] Figure 2A schematic diagram of the connection relationship of the first liquid level control system proposed in an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of a first connection relationship between an electric heater and a compressor housing proposed in an embodiment of the present invention;

[0029] Figure 4 A schematic diagram of the structure of a compressor housing according to an embodiment of the present invention;

[0030] Figure 5 A schematic diagram of a second connection relationship between the electric heater and the compressor housing proposed in an embodiment of the present invention;

[0031] Figure 6 A structural cross-sectional view of a first liquid level control system proposed in an embodiment of the present invention;

[0032] Figure 7 A structural cross-sectional view of a second liquid level control system proposed in an embodiment of the present invention;

[0033] Figure 8 A structural cross-sectional view of a third liquid level control system proposed in an embodiment of the present invention;

[0034] Fig. 9 A control logic diagram of a first liquid level control system proposed in an embodiment of the present invention;

[0035] Fig.10 A schematic diagram of the structure of a compressor provided in an embodiment of the present invention;

[0036] The description of each reference numeral is as follows:

[0037] 1-float control unit; 11-slide bar; 12-float; 13-reed switch; 14-first float control unit; 15-second float control unit; 16-third float control unit;

[0038] 2-electric heater; 21-protrusion;

[0039] 3-Inverter; 4-Relay;

[0040] 5-compressor housing; 51-accommodation groove; 52-guide groove; 53-protrusion; 531-straight section; 532-curved section;

[0041] X-axial direction; Y-circumferential direction. DETAILED DESCRIPTION

[0042] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0043] As used in this specification, the singular forms "a", "an" and "the" include plural objects, the term "or" is generally used to include the meaning of "and / or", the term "several" is generally used to include the meaning of "at least one", and the term "at least two" is generally used to include the meaning of "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, "one end" and "the other end" and "the proximal end" and "the distal end" generally refer to two corresponding parts, which include not only the endpoints, and the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. In addition, as used in this specification, an element disposed on another element generally only indicates that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the connection, coupling, cooperation or transmission between the two elements may be direct or indirect through an intermediate element, and it cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, one element may be in any orientation such as inside, outside, above, below or on one side of another element, unless the content clearly indicates otherwise. The terms "upper", "lower", "top" and "bottom" are generally relative position relationships arranged in the direction of gravity; the terms "vertical, vertical direction" generally refer to the direction of gravity, which is generally perpendicular to the ground, and "horizontal, horizontal plane direction" generally refers to the direction parallel to the ground; for ordinary technicians in this field, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0044] The object of the present invention is to provide a liquid level control system and a compressor to solve the problem of poor lubrication and subsequent failure of the compressor caused by reasons such as low-frequency operation of the compressor or refrigerant migration when the compressor is shut down in a low-temperature environment.

[0045] Those skilled in the art can understand that in the daily use of refrigeration equipment, when the compressor is in low-frequency operation, the lubricating oil is retained in the system pipeline, which will cause the internal liquid level of the compressor to be lower than the safety line; or the refrigeration equipment is shut down for a long time in a low-temperature environment, causing the refrigerant to flow to the compressor, which will cause the internal liquid level of the compressor to rise and dilute the lubricating oil. Both of the above situations will cause the compressor to be poorly lubricated during operation, which will easily cause the compressor to fail. Based on this, the present application provides a liquid level control system, which is electrically connected to a functional device (such as an electric heater or a frequency converter) through a float control unit. After the internal liquid level of the compressor reaches a preset position, the functional device is operated to raise or lower the internal liquid level of the compressor to ensure that the liquid level is always within a safe range. It should be noted that the present application is only illustrated by refrigeration equipment (such as air conditioners, coolers, etc.) as an example. This does not mean that the liquid level control system proposed in the present application can only be applied to the compressor of the refrigeration equipment. As long as the liquid level needs to be controlled and different measures are adopted at different liquid levels, such as automobiles, water treatment systems, etc., the above system can be used, and this embodiment is not limited to this.

[0046] Please refer to Figure 1 to Figure 2 The present invention provides a liquid level control system, including: a float control unit 1, an electric heater 2, and a frequency converter 3; the float control unit 1 is electrically connected to the electric heater 2 or the frequency converter 3, the electric heater 2 is used to increase the temperature of the oil pool inside the compressor housing 5, and the frequency converter 3 is used to adjust the motor speed; the float control unit 1 is configured to: be turned on when the internal liquid level of the compressor reaches a preset position, drive the electric heater 2 or the frequency converter 3 to operate, so that the internal liquid level of the compressor is always within a safe range; wherein the liquid level control system also includes an installation device, and the electric heater 2 is installed inside the compressor housing 5 through the installation device. Those skilled in the art can understand that in some other embodiments, the electric heater 2 can also be installed on the outside of the compressor housing. For example, the electric heater 2 can be a strip-shaped member and directly wound around the outside of the compressor housing 5. Heat is transferred through the compressor housing 5 to heat the oil pool. At this time, an insulating layer (which can be insulating rubber or other insulating devices) needs to be coated on the outer surface of the electric heater 2 to ensure the insulation of the electric heater 2. In this embodiment, the electric heater 2 is directly installed inside the compressor housing 5 through a mounting device to directly heat the oil pool. At this time, in order to solve the isolation problem between the electric heater 2 and the refrigerant and lubricating oil, the electric heater 2 can be encapsulated in a metal ring tube or a plastic ring tube (such as Figures 3 to 5As shown), the metal ring tube can be made of steel, copper or aluminum, and the plastic ring tube can be made of PBT (polybutyleneterephthalate) plastic. In this configuration, the electric heater 2 is arranged inside the compressor housing 5 to directly heat the oil pool, which reduces the heat transfer process through the compressor housing 5 and reduces the loss of heat generated by the electric heater 2 during the transfer process, so that the liquid temperature in the oil pool can be increased more quickly, thereby improving the working efficiency of the liquid level control system. In other embodiments, the electric heater 2 can also be a plate-like component, and is arranged outside or inside the compressor housing 5 by mechanical connection or welding.

[0047] In an optional embodiment, the float control unit 1 is arranged inside the compressor, and includes a float 12, a slide bar 11 and a reed switch 13, wherein the slide bar 11 is arranged parallel to the axial direction X of the compressor, the float 12 and the reed switch 13 are located on the slide bar 11, and the float 12 can move up and down along the axial direction X of the slide bar 11 within a preset position range including a preset position, the reed switch 13 is set at a preset position, and a magnet is provided inside the float 12, which can drive the reed switch 13 to close when moving to the preset position, thereby achieving conduction, thereby driving the electric heater 2 or the inverter 3 to operate. It should be noted that the liquid inside the compressor is lubricating oil or a mixture of lubricating oil and refrigerant. The gravity of the float 12 is lower than the buoyancy provided by the liquid inside the compressor. Therefore, the float 12 can move within the preset position range as the liquid level rises and falls; and the preset position range can be determined by installing a limit block on the slide bar 11 (the limit block is sleeved on the slide bar 11 and fixedly connected to the slide bar 11) to limit the displacement of the float 12 along the axial direction X of the slide bar 11. The float 12 usually only moves within a short distance above and below the preset position (for example, within a range of tens of millimeters above and below the preset position), thereby improving the durability of the float 12 and avoiding wear or jamming of the float 12 during long-distance movement, thereby failing to control the closing of the reed switch 13, resulting in the possibility of failure of the float control unit 1.

[0048] With such configuration, technicians can set different numbers of float control units 1 and connect them to different functional devices (electric heater 2 and frequency converter 3 in this embodiment) to achieve control of the internal liquid level of the compressor. For example, by setting the float control unit 1 at the upper limit of the safety range and electrically connecting it to the electric heater 2, when the internal liquid level of the compressor exceeds the upper limit of the safety range, the float 12 drives the magnetic reed switch 13 to close, and the electric heater 2 runs to heat to lower the liquid level; or by setting the float control unit 1 at the lower limit of the safety range and electrically connecting it to the frequency converter 3, when the internal liquid level of the compressor is lower than the lower limit of the safety range, the float 12 drives the magnetic reed switch 13 to close, and the frequency converter 3 runs and increases the motor speed, and increases the refrigerant flow rate to bring back the lubricating oil retained in the system pipeline, thereby raising the liquid level. This ensures that the internal liquid level of the compressor is always within the safety range, avoiding the situation where the internal liquid level is too high or too low, causing poor lubrication of the compressor and thus failure.

[0049] Furthermore, the mounting device includes a snap-fit ​​mechanism, and the electric heater 2 is snap-fitted and connected to the snap-fit ​​mechanism. It should be noted that in the present embodiment, the snap-fit ​​structure is provided on the inner wall of the compressor housing 5, and the electric heater 2 is snap-fitted and connected to the snap-fit ​​mechanism to fix the electric heater 2 inside the compressor housing 5. Of course, in some other embodiments, the electric heater 2 can also be threadedly connected by providing a threaded section on the inner wall of the compressor housing 5, or a magnetic attraction mechanism is provided on the inner wall of the compressor housing 5 to achieve a magnetic attraction connection. Those skilled in the art can configure this according to actual conditions.

[0050] As an alternative embodiment, please refer to Figure 3 and Figure 4 The engaging mechanism includes a receiving groove 51 and a plurality of guide grooves 52. Both the receiving groove 51 and the guide groove 52 are located on the inner wall of the compressor housing 5. The receiving groove 51 is arranged along the circumferential direction Y of the compressor housing 5, and the guide groove 52 is arranged along the axial direction X of the compressor housing 5. The plurality of guide grooves 52 are arranged at intervals along the circumferential direction Y of the compressor housing 5, and one end of the guide groove 52 is connected with the receiving groove 51. The outer periphery of the electric heater 2 is provided with a plurality of protrusions 21 adapted to the guide grooves 52. The protrusions 21 are arranged in correspondence with each other in the guide grooves 52, and after the guide grooves 52 are inserted into the receiving grooves 51, they are rotated by a preset angle along the circumferential direction Y of the compressor housing 5 to realize the connection between the electric heater 2 and the compressor housing 5. It should be noted that the preset angle needs to be smaller than the angle between the lines connecting two adjacent guide grooves 52 and the center of the bottom surface of the compressor. In this way, the engagement connection between the electric heater 2 and the compressor housing 5 is realized through the cooperation between the protrusions 21, the guide grooves 52 and the receiving grooves 51. Of course, in other embodiments, the cross-sectional shape of the compressor housing 5 may also be a rectangle, a quadrilateral or other shapes, and accordingly, the electric heater 2 may also be packaged in a tubular component that is compatible therewith.

[0051] In another embodiment, please refer to Figure 5 The engaging mechanism includes a plurality of protrusions 53, which extend toward the interior of the compressor housing 5 and are welded to the inner wall of the compressor housing 5. The plurality of protrusions 53 are arranged at intervals along the circumferential direction Y of the compressor housing 5, and the electric heater 2 is engaged with the protrusions 53. Figure 5 In the illustrated example, the protrusion 53 has a straight section 531 and a curved section 532. One end of the straight section 531 is welded to the inner wall of the compressor housing 5, and the other end is connected to the curved section 532. The curvature of the curved section 532 matches the curvature of the outer wall of the electric heater 2, thereby further increasing the contact area between the protrusion 53 and the electric heater 2, thereby increasing the connection strength between the electric heater 2 and the inner wall of the compressor housing 5.

[0052] As an alternative embodiment, please refer to Figure 2 and Figure 6 The liquid level control system includes a first float control unit 14 and a second float control unit 15; the first float control unit 14 is electrically connected to the electric heater 2, and the first float control unit 14 is configured to: turn on when the internal liquid level of the compressor reaches a first preset position, drive the electric heater 2 to operate, so as to increase the oil pool temperature inside the compressor housing 5; the second float control unit 15 is electrically connected to the frequency converter 3, and the second float control unit 15 is configured to: turn on when the internal liquid level of the compressor reaches a second preset position, drive the frequency converter 3 to operate, so as to adjust the motor speed. It should be noted that Figure 2 and Figure 6In the illustrated example, the first preset position is the upper limit of the safety range. When the refrigeration equipment is shut down for a long time in a low-temperature environment, the refrigerant flows back to the compressor, causing the internal liquid level of the compressor to rise. When the internal liquid level of the compressor rises to the first preset position, the float 12 drives the reed switch 13 located at the first preset position to close, turning on the circuit connected to the electric heater 2, and then driving the electric heater 2 to heat the oil pool inside the compressor housing 5, thereby increasing the oil pool temperature and the oil pool superheat, so that the oil pool temperature is increased to the evaporation temperature of the refrigerant (those skilled in the art can understand that the evaporation temperature of the refrigerant is lower than the evaporation temperature of the lubricating oil, and the evaporation temperature is related to the pressure. Under normal circumstances, the evaporation temperature of the refrigerant is 50° to 60°, The maximum working temperature of the lubricating oil can reach nearly 200°), so as to release the refrigerant and reduce the internal liquid level of the compressor to a safe range; the second preset position is the lower limit of the safety range. When the compressor is running at a low frequency, the gas circulation speed is low, and the lubricating oil is retained in the system pipeline, causing the internal liquid level of the compressor to drop. When the internal liquid level of the compressor drops to the second preset position, the float 12 drives the reed switch 13 located at the second preset position to close, and turns on the circuit connected to the inverter 3, thereby driving the inverter 3 to increase the motor speed, thereby increasing the gas circulation speed in the system pipeline, and bringing the lubricating oil retained in the system pipeline back to the oil pool of the compressor, so as to raise the internal liquid level of the compressor to a safe range, and also improve the oil pumping effect.

[0053] Furthermore, the first preset position includes: 0mm to 40mm from the lower core surface of the compressor stator or 0mm to 40mm from the upper core surface of the compressor stator; the second preset position includes: 0mm to 10mm above the dust collecting ring of the compressor. It should be noted that the distance from the first preset position to the bottom of the compressor is Figure 6 D2 in the figure, the distance from the second preset position to the bottom of the compressor is Figure 6 D1 in the figure, the safety range is that the internal liquid level of the compressor is between D1 and D2, at which time the compressor can ensure good lubrication, thereby extending the service life and reducing the cost of production and subsequent maintenance. Of course, in other embodiments, the first preset position and the second preset position can also be set at other positions inside the compressor, and those skilled in the art can reasonably set the preset positions according to different actual monitoring requirements and different internal structures of different compressors.

[0054] In another embodiment, please refer to Figure 7 The liquid level control system further includes a third float control unit 16 and an alarm unit (not shown in the figure); the third float control unit 16 is electrically connected to the alarm unit, and the third float control unit 16 is configured to: conduct when the internal liquid level of the compressor reaches a third preset position, and drive the alarm unit to send an alarm signal. Figure 7In the exemplary embodiment shown, the liquid level control system comprises three float control units 1, in addition to Figure 6 In addition to the first float control unit 14 placed at the first preset position and the second float control unit 15 placed at the second preset position shown in the figure, there is also a third float control unit 16 arranged on the top of the compressor, which is connected to the alarm unit (which can be a buzzer alarm light, etc.), and can send out an alarm signal (which can be a sound signal and / or a light signal) to notify the technician when the liquid level continues to rise after the first float unit 12 drives the electric heater 2 to heat the oil pool; of course, in other embodiments, the third float control unit 16 can also be set at the bottom of the compressor, and it can send out an alarm signal when the liquid level continues to drop after the second float unit 12 drives the inverter 3 to increase the motor speed. With such a configuration, the third float control unit 16 can monitor the control effect of the first float unit 12 and the second float unit 12. Of course, the third float control unit 16 can also be set at another liquid level that needs to be controlled and electrically connected to another functional device. Those skilled in the art can configure this according to actual conditions.

[0055] As another alternative embodiment, please refer to Figure 8 The liquid level control system may also include only one float control unit 1, which may be arranged in a Figure 6 The first preset position or the second preset position shown in the figure is electrically connected to the electric heater 2 or the frequency converter 3; it can also be set at other liquid levels that need to be controlled and electrically connected to other functional devices. In other embodiments, the float control unit 1 can also be configured to be four or more according to the number of liquid levels that need to be controlled, which is not limited in this embodiment.

[0056] Please refer to Figure 2 and Fig. 9 The liquid level control system further includes a relay 4, through which the float control unit 1 is electrically connected to the electric heater 2 or the frequency converter 3, and the relay 4 is configured to send a heating instruction to the electric heater or a speed control instruction to the frequency converter 3 when the float control unit 1 is turned on. It should be noted that in this embodiment, the relay 4 is connected to the electric heater 2 and the frequency converter 3 as a control unit, respectively. In other optional embodiments, the control unit may also be a host with a built-in chip, which can communicate with the electric heater 2 and the frequency converter 3 to achieve control. Those skilled in the art may reasonably configure the control unit according to actual conditions.

[0057] Please refer to Figure 1 and Fig.10The present invention also provides a compressor, including a compressor housing 5, an oil pool (not shown in the figure) and the liquid level control system as described above; the oil pool is arranged inside the compressor housing 5, and the float control unit 1 is arranged inside the oil pool. The float control unit 1 drives the electric heater 2 or the inverter 3 to operate based on the rise and fall of the liquid level in the oil pool, so that the liquid level in the oil pool is always within a safe range. With such a configuration, the compressor provided with a liquid level control system can realize the control of the internal liquid level of the compressor by assembling different numbers of float control units 1 and connecting them with different functional devices respectively, thereby ensuring that the internal liquid level of the compressor is always within a safe range, avoiding the situation where the internal liquid level is too high or too low, causing poor lubrication of the compressor and thus failure.

[0058] In summary, in the liquid level control system and the compressor provided in the embodiments of the present invention, the liquid level control system includes: a float control unit, an electric heater, and a frequency converter; the float control unit is electrically connected to the electric heater or the frequency converter, the electric heater is used to increase the temperature of the oil pool inside the compressor casing, and the frequency converter is used to adjust the motor speed; the float control unit is configured to: be turned on when the internal liquid level of the compressor reaches a preset position, and drive the electric heater or the frequency converter to operate, so that the internal liquid level of the compressor is always within a safe range.

[0059] With such configuration, technicians can control the internal liquid level of the compressor by assembling different numbers of float control units and connecting them to different functional devices. For example, a float control unit is set at the upper limit and the lower limit of the safety range respectively. When the internal liquid level exceeds the upper limit of the safety range, the electric heater is driven to heat it; when the internal liquid level exceeds the lower limit of the safety range, the inverter is driven to increase the operating frequency of the compressor, so as to ensure that the internal liquid level of the compressor is always within the safe range, avoiding the situation where the internal liquid level is too high or too low, causing poor lubrication of the compressor and thus failure; in addition, the electric heater is set inside the compressor casing to directly heat the oil pool. Compared with the solution of setting it outside the compressor casing and transferring heat through the compressor casing, the heat transfer steps are reduced, the heat loss in the transfer process is reduced, and the working efficiency of the liquid level control system is improved.

[0060] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A liquid level control system, characterized in that: include: Float control unit, electric heater, inverter; The float control unit is electrically connected to the electric heater or the frequency converter, the electric heater is used to increase the temperature of the oil pool inside the compressor housing, and the frequency converter is used to adjust the motor speed; The float control unit is configured to: conduct when the internal liquid level of the compressor reaches a preset position, drive the electric heater or the inverter to operate, so that the internal liquid level of the compressor is always within a safe range; Wherein, the liquid level control system further comprises a mounting device, and the electric heater is mounted inside the compressor housing through the mounting device.

2. The liquid level control system according to claim 1, characterized in that: The mounting device comprises a snap-fit ​​mechanism, and the electric heater is snap-fitted and connected to the snap-fit ​​mechanism.

3. The liquid level control system according to claim 2, characterized in that: The engaging mechanism comprises a receiving groove and a plurality of guiding grooves, both of which are located on the inner wall of the compressor housing, the receiving groove is arranged along the circumferential direction of the compressor housing, the guiding groove is arranged along the axial direction of the compressor housing, a plurality of guiding grooves are arranged at intervals along the circumferential direction of the compressor housing, and one end of the guiding groove is connected to the receiving groove; A plurality of protrusions matching the guide grooves are provided on the outer circumference of the electric heater. The protrusions are passed through the guide grooves one by one, and after passing through the accommodating grooves from the guide grooves, they are rotated by a preset angle along the circumference of the compressor housing to achieve the connection between the electric heater and the compressor housing.

4. The liquid level control system according to claim 2, characterized in that: The locking mechanism includes a plurality of protrusions, which extend toward the interior of the compressor housing and are welded to the inner wall of the compressor housing. The plurality of protrusions are arranged at intervals along the circumference of the compressor housing, and the electric heater is locked and connected to the protrusions.

5. The liquid level control system according to claim 1, characterized in that: The electric heater is encapsulated in a metal ring tube or a plastic ring tube.

6. The liquid level control system according to claim 1, characterized in that: The liquid level control system includes a first float control unit and a second float control unit; The first float control unit is electrically connected to the electric heater, and the first float control unit is configured to: turn on when the internal liquid level of the compressor reaches a first preset position, drive the electric heater to operate, so as to increase the temperature of the oil pool inside the compressor housing; The second float control unit is electrically connected to the frequency converter, and is configured to be turned on when the internal liquid level of the compressor reaches a second preset position, and drive the frequency converter to operate so as to adjust the motor speed.

7. The liquid level control system according to claim 6, characterized in that: The first preset position includes: 0mm to 40mm away from the lower core surface of the stator of the compressor or 0mm to 40mm away from the upper core surface of the stator of the compressor; the second preset position includes: 0mm to 10mm above the dust collecting ring of the compressor.

8. The liquid level control system according to claim 6, characterized in that: The liquid level control system also includes a third float control unit and an alarm unit; The third float control unit is electrically connected to the alarm unit, and the third float control unit is configured to be turned on when the internal liquid level of the compressor reaches a third preset position, and drive the alarm unit to send an alarm signal.

9. The liquid level control system according to claim 1, characterized in that: The liquid level control system also includes a relay, and the float control unit is electrically connected to the electric heater or the frequency converter through the relay. The relay is configured to send a heating instruction to the electric heater or a speed control instruction to the frequency converter when the float control unit is turned on.

10. A compressor, characterized in that: It comprises a compressor housing, an oil pool and a liquid level control system as claimed in any one of claims 1 to 9; The oil pool is arranged inside the compressor housing, and the float control unit is arranged inside the oil pool. The float control unit drives the electric heater or the inverter to operate based on the rise and fall of the liquid level in the oil pool, so that the liquid level in the oil pool is always within a safe range.

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