Rotary compressor

Abstract

The present invention provides a rotary compressor, comprising: a housing including a lubricating oil storage portion for accommodating lubricating oil; a compression mechanism; the driving mechanism is used for driving the compression mechanism, the driving mechanism comprises a rotating shaft, an oil hole extending in the axial direction of the rotating shaft is formed in the rotating shaft, and the lubricating oil from the lubricating oil storage part can be supplied to the oil hole; the rotary compressor further comprises an oil discharge valve, the oil discharge valve is fixedly connected to the base, and the oil discharge valve is in fluid communication with the oil hole through an oil discharge channel. According to the rotary compressor, oil circulation can be kept within a reasonable range under different rotating speed conditions, and operation is stable and reliable.

Description

Technical Field

[0001] The present invention relates to a rotary compressor, and more particularly to a variable frequency compressor having an oil circulation regulating mechanism. Background Art

[0002] This section provides background information related to the present invention, which does not necessarily constitute prior art.

[0003] In this article, a rotary compressor refers to a machine compressor having a rotating shaft, a crankshaft or a rotating drive shaft, such as a scroll compressor. The scroll compressor includes a compression mechanism for compressing a working fluid and a rotating shaft for driving the compression mechanism. Generally, the oil circulation process of a scroll compressor system includes: an oil pump supplies lubricating oil in an oil sump to various moving parts (including bearings, cross slip rings, bushings, scrolls, etc.) or thrust surfaces of the compressor through internal oil holes of the rotating shaft, so as to achieve lubrication and cooling. Subsequently, part of the lubricating oil transported to the upper part of the compressor falls back into the oil sump under the action of gravity; another part of the lubricating oil is entrained by the refrigerant gas and discharged from the exhaust port of the compressor into the system, and part of the lubricating oil entering the system is entrained by the refrigerant gas and returns to the compressor from the suction port of the compressor.

[0004] The oil circulation of the compressor needs to be maintained within a reasonable range. Too low is likely to cause insufficient lubrication of components such as scrolls and bearings, thus affecting the performance and service life of the compressor; too high will cause excessive lubricating oil to be discharged from the compressor, resulting in lack of lubrication of the compressor and reduction of system efficiency.

[0005] For a variable frequency compressor, since the speed range of the compressor is relatively wide and the oil pumping volume of the oil pump is proportional to the speed, therefore, when it is necessary to increase the oil circulation under low-speed operation of the compressor, the oil circulation under high-speed operation of the compressor will increase exponentially, resulting in too high an oil circulation under high-speed operation of the compressor; when it is necessary to reduce the oil circulation under high-speed operation of the compressor, the oil circulation under low-speed operation of the compressor will decrease exponentially, resulting in too low an oil circulation under low-speed operation of the compressor.

[0006] Therefore, the present invention expects to provide a rotary compressor capable of balancing the oil circulation under different speed states, so as to keep the oil circulation of the compressor within a reasonable range under different speed states. Summary of the Invention

[0007] In this section, a general overview of the present invention is provided, rather than a complete disclosure of the full scope of the present invention or all features of the present invention.

[0008] One object of the present invention is to provide a mechanism capable of adjusting the lubricating oil circulation of a compressor under different operating conditions, especially an adjusting mechanism that can avoid excessive oil circulation in the compressor when the compressor operates at a high rotational speed.

[0009] Another object of the present invention is to provide a rotary compressor, especially a variable frequency compressor, which can achieve balanced oil supply within the full rotational speed range and keep the oil circulation of the compressor within a reasonable range under different rotational speed conditions.

[0010] The present invention provides a rotary compressor, including: a housing, the housing includes a lubricating oil storage part for accommodating lubricating oil; a compression mechanism; a driving mechanism for driving the compression mechanism, the driving mechanism includes a rotating shaft, and an oil hole extending along the axial direction of the rotating shaft is provided in the rotating shaft, and the lubricating oil from the lubricating oil storage part can be supplied to the oil hole; and a base, the base is equipped with the rotating shaft, wherein the rotary compressor further includes an oil discharge valve, the oil discharge valve is fixedly connected to the base, and the oil discharge valve is in fluid communication with the oil hole through an oil discharge channel.

[0011] Optionally, the oil discharge channel includes: one or more oil discharge holes extending through the side wall of the rotating shaft and in fluid communication with the oil hole, a circumferential oil groove formed between the rotating shaft and the base and in fluid communication with the oil discharge holes, and an oil discharge interface extending through the base and in fluid communication with the circumferential oil groove and the oil discharge valve; or the oil discharge channel includes: one or more oil discharge holes extending through the side wall of the rotating shaft and in fluid communication with the oil hole and an oil discharge interface extending through the base and capable of being in fluid communication with the oil discharge holes and the oil discharge valve.

[0012] Optionally, the circumferential oil groove is formed by partially recessing the outer surface of the rotating shaft towards the radially inner side, and / or the circumferential oil groove is formed by partially recessing the inner surface of the base towards the radially outer side.

[0013] Optionally, the oil discharge valve includes a substantially cylindrical outer shell and a valve stopper capable of moving along the axial direction of the oil discharge valve within the space surrounded by the outer shell, one end of the oil discharge valve is configured to be closed, the opposite end of the oil discharge valve is configured to have an inlet and is connected to the oil discharge interface, and the outer shell is provided with one or more oil discharge holes extending through the outer shell.

[0014] Optionally, the rotary compressor further includes an oil supply pipe, the oil supply pipe is fixedly connected to the base, and is in fluid communication with the oil hole through the oil discharge channel.

[0015] Optionally, the oil drainage passage includes: one or more oil drainage holes extending through the side wall of the rotating shaft and in fluid communication with the oil holes, a circumferential oil groove formed between the rotating shaft and the base and in fluid communication with the oil drainage holes, an oil discharge interface extending through the base and in fluid communication with the circumferential oil groove and the oil discharge valve, and an oil supply interface extending through the base and in fluid communication with the circumferential oil groove and the oil supply pipe; or the oil drainage passage includes: one or more oil drainage holes extending through the side wall of the rotating shaft and in fluid communication with the oil holes, an oil discharge interface extending through the base and capable of being in fluid communication with the oil drainage holes and the oil discharge valve, and an oil supply interface extending through the base and in fluid communication with the oil drainage holes and the oil supply pipe.

[0016] Optionally, the first port of the oil supply pipe is connected to the base, and the second port of the oil supply pipe opposite to the first port is higher than the oil discharge valve.

[0017] Optionally, the housing is provided with an air inlet, and the second port is arranged near the air inlet.

[0018] Optionally, the oil supply interface is higher than the oil discharge valve.

[0019] Optionally, the flow area of the oil supply pipe is smaller than the flow area of the oil discharge valve.

[0020] Optionally, the first port of the oil supply pipe is connected to the base, and an adjustment nozzle is arranged at the second port of the oil supply pipe opposite to the first port to adjust the flow rate in the oil supply pipe.

[0021] Optionally, the oil supply pipe is provided with a separate on-off valve.

[0022] Optionally, the circumferential oil groove extends 360° circumferentially, or the circumferential oil groove extends less than 360° circumferentially such that the oil discharge interface and the oil drain interface can be in communication via the circumferential oil groove.

[0023] Optionally, the rotary compressor is a variable-frequency scroll compressor.

[0024] Generally, the oil circulation regulating mechanism according to the present invention and the rotary compressor employing the oil circulation regulating mechanism at least bring the following beneficial effects: when the rotary compressor operates at a low speed, sufficient oil supply can be ensured to provide sufficient lubrication and cooling, thereby maintaining the performance and reliability of the rotary compressor during low-speed operation; when the rotary compressor operates at a high speed, excessive oil supply can be prevented, thereby avoiding reduction in the energy efficiency and reliability of the rotary compressor; in addition, according to the different operating speeds of the rotary compressor, the oil circulation can be basically adjusted adaptively, thereby achieving a balanced oil circulation of the rotary compressor within the full speed range; in addition, the oil circulation regulating mechanism (including the oil discharge valve, the oil supply pipe, etc.) of the rotary compressor is installed in a fixed manner, with better reliability, and is simple in manufacturing and processing, easy to replace and repair, and low in cost. Description of the Drawings

[0025] The foregoing and additional features and characteristics of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, which are presented by way of example only and are not necessarily to scale. Identical reference numerals in the drawings indicate identical components, and in the drawings:

[0026] Figure 1 A longitudinal sectional view of a scroll compressor according to a first embodiment of the present invention is shown;

[0027] Figure 2 is Figure 1 A perspective schematic view of part A in [the figure], wherein a circumferential part of part A is removed to show the oil discharge passage;

[0028] Figure 3 A perspective schematic view of a base according to a first embodiment of the present invention is shown;

[0029] Figure 4 A perspective schematic view of a base according to a first embodiment of the present invention is shown, wherein a circumferential part of the base is removed;

[0030] Figure 5 A longitudinal sectional view of a base according to a first embodiment of the present invention is shown;

[0031] Figure 6a A perspective schematic view of a rotating shaft according to a first embodiment of the present invention is shown;

[0032] Figure 6b A perspective schematic view of the lower end portion of a rotating shaft according to a first embodiment of the present invention is shown, wherein a circumferential part of the lower end portion is removed;

[0033] Figure 7 A perspective schematic view of an oil discharge valve according to a first embodiment of the present invention is shown;

[0034] Figure 8 A longitudinal sectional view of an oil discharge valve according to a first embodiment of the present invention is shown;

[0035] Figure 9 A perspective schematic view of a valve plate of an oil discharge valve according to a first embodiment of the present invention is shown;

[0036] Figure 10 A longitudinal sectional view of an oil supply joint according to a first embodiment of the present invention is shown;

[0037] Figure 11 A longitudinal sectional view of a base according to a second embodiment of the present invention is shown;

[0038] Figure 12aA three-dimensional schematic view of a rotating shaft according to a second embodiment of the present invention is shown; and

[0039] Figure 12b A three-dimensional schematic view of a lower end portion of a rotating shaft according to a second embodiment of the present invention is shown, wherein a part of the lower end portion in the circumferential direction is removed. Detailed Embodiment

[0040] Now, in conjunction with Figures 1 to 12b Preferred embodiments of the present invention will be described in detail. In each view, corresponding components or parts are denoted by the same reference numerals. The following description is merely exemplary in nature and is not intended to limit the present invention and its application or use. In the drawings, the rotary compressor is shown as a vertical variable-frequency scroll compressor, but those skilled in the art will understand that the oil circulation regulating mechanism according to the present invention is applicable to any other suitable type of mechanical equipment or system having a rotating shaft, a crankshaft, or a rotating rotating shaft, and is applicable not only to a vertical compressor with a vertically oriented rotating shaft but also to a horizontal compressor with a horizontally oriented rotating shaft.

[0041] First, with reference to Figure 1 The overall structure and operating principle of a scroll compressor according to the present invention will be described. The rotary compressor 100 includes a housing 10 that encloses an internal space of the compressor. The housing 10 includes a substantially cylindrical housing body 12, a top cover 14 fixedly connected to one end of the housing body 12 (shown as the upper end in Figure 1 ), and a bottom cover 16 fixedly connected to the other end of the housing body (shown as the lower end in Figure 1 ). An intake port 17 is provided on the housing body 12 for sucking in low-pressure gaseous refrigerant. An exhaust port 15 is provided on the top cover 14 for discharging the compressed refrigerant. A sound insulation plate 13 that extends laterally in the axial direction of the housing body 12 (extends in a substantially horizontal direction in Figure 1 ) is further provided between the housing body 12 and the top cover 14, thereby dividing the internal space of the compressor into a high-pressure side and a low-pressure side. The space between the top cover 14 and the sound insulation plate 13 constitutes a high-pressure side space, and the space between the sound insulation plate 13, the housing body 12, and the bottom cover 16 constitutes a low-pressure side space. A part of the low-pressure side space constitutes a lubricating oil storage portion 18 for storing lubricating oil. In the example of Figure 1 , the lubricating oil storage portion 18 is located at the bottom of the housing 10.

[0042] The internal space of the compressor (shown as the low-pressure side space in Figure 1 ) houses a compression mechanism 20 and a drive mechanism DM. In Figure 1In the illustrated example, the compression mechanism 20 includes a fixed scroll member 22 and a moving scroll member 24 that mesh with each other. The drive mechanism DM includes a rotating shaft 30 and a motor 50. The motor 50 includes a stator 51 and a rotor 52. The rotor 52 is fixedly connected to the rotating shaft 30 and rotates within the stator 52. The first end of the rotating shaft 30 ( Figure 1 the upper end in

[0043] this case) is provided with an eccentric crank pin 32, and the eccentric crank pin 32 is inserted into the hub portion 26 of the moving scroll member 24. By driving the motor 50, the rotating shaft 30 causes the moving scroll member 24 to perform a orbiting motion relative to the fixed scroll member 22 via the eccentric crank pin, so as to compress the working fluid. Figure 1 The first end of the rotating shaft 30 (the upper end in Figure 1 this case) is supported by the main bearing block 40, while the second end (the lower end in

[0044] this case, that is, at the end of the rotating shaft 30 close to the lubricating oil storage portion 18) is assembled in a base (lower bearing block) 70. The main bearing block 40 and the base 70 can be fixedly connected to a fixed member, such as the housing body 12, in a suitable manner. A pump oil mechanism 74, such as a positive displacement oil pump, can also be provided at the second end of the rotating shaft 30.

[0045] An oil hole 34 extending substantially axially is formed in the rotating shaft 30. The oil hole 34 can include a central hole section formed at the second end of the rotating shaft 30 (the central hole section is substantially concentric with the rotating shaft) and an eccentric hole section extending upward from the central hole section to the end face of the eccentric crank pin 32. During the operation of the compressor, the lubricating oil in the lubricating oil storage portion 18 is supplied into the central hole section formed at the lower end of the rotating shaft 30 of the oil hole 34. The lubricating oil entering the central hole section is pumped or thrown into the eccentric hole section under the action of centrifugal force during the rotation of the rotating shaft 30 and flows upward along the eccentric hole section until it reaches the end face of the eccentric crank pin 32. The lubricating oil discharged from the end face of the eccentric crank pin 32 is used to lubricate and cool the eccentric crankshaft pin 32 and various moving parts near the hub portion 26 of the moving scroll. Subsequently, a part of the lubricating oil transported to the upper part of the compressor returns to the lubricating oil storage portion 18 under the action of gravity, and another part is entrained by the refrigerant gas and enters the compression mechanism 20 and is discharged from the exhaust port 15 of the compressor and enters the system. A part of the lubricating oil entering the system returns to the compressor with the refrigerant from the intake port 17 of the compressor. Thus, the oil circulation of the compressor is constituted.Those skilled in the art can understand that the oil circulation of the compressor needs to be maintained within a reasonable range. If the oil circulation rate of the compressor is low, it is easy to cause insufficient lubrication of components such as scrolls and bearings, thus affecting the performance and lifespan of the compressor; if the oil circulation of the compressor is too high, it will cause excessive lubricating oil of the compressor to be discharged from the exhaust port of the compressor, resulting in a lack of lubricating oil inside the compressor, which also affects the performance and lifespan of the compressor. On the other hand, particularly for a variable-frequency compressor, the change range of the rotational speed of the compressor is relatively large, and the oil pumping volume of the positive-displacement oil pump commonly used in the variable-frequency compressor is proportional to the rotational speed of the compressor, which means that the oil pumping volume of the compressor in the high-speed state is much larger than that in the low-speed state. Therefore, it is difficult to maintain the oil circulation of the compressor in different rotational speed states within a reasonable range. In view of this, in order to achieve the balance of the oil circulation of the compressor in different rotational speed states, the present invention proposes that the rotary compressor 100 is provided with an oil circulation adjustment mechanism, such as Figure 1 shown in part A of

[0046] The oil circulation adjustment mechanism is generally arranged at the lower part of the rotary compressor 100, that is, at the position of the second end of the rotating shaft 30 and the base 70. At this position, the second end of the rotating shaft 30 is inserted into the central through hole 71 of the base 70 and is supported by a bearing 72 (see Figure 2 ) arranged inside the central through hole 71 of the base 70 (for example, arranged in the upper part of the central through hole). As shown in Figure 3 , Figure 4 , Figure 5 , the central through hole 71 of the base 70 is defined by the inner surface 73 of the base 70. The inner surface 73 can be divided into a first surface part for installing the bearing 72 (the upper part in Figure 4 ) and a second surface part where the bearing 72 is not installed (the lower part in Figure 4 ). Among them, as shown in Figure 3 , 4 , the second surface part can at least partially recess toward the radially outer side, thereby forming a circumferential oil groove 79. The recessed distance (radial distance) can be equal to the radial thickness of the bearing 72, so as to form a smooth vertical plane with the first surface part for easy processing. The base 70 is also formed with an oil discharge interface 76 that extends through the base 70 (that is, extends from the inner surface of the base 70 to the outer surface of the base 70) and is in fluid communication with the circumferential oil groove 79. Preferably, the oil discharge interface 76 is arranged in the area where the circumferential oil groove 79 is formed in the second surface part, so as to facilitate fluid communication with the circumferential oil groove 79 and facilitate processing.

[0047] As shown in Figure 2 , Figure 6a , Figure 6bAs shown, the second end of the rotating shaft 30 includes a shaft head 31 inserted and mounted into the base 70. A part of the shaft head 31 in the axial direction (the upper part in Figure 2 is arranged to face the first surface part of the inner surface 73 of the base 70, contact the bearing 72 and form a support. Another part of the shaft head 31 in the axial direction (the lower part in Figure 2 is arranged to face the second surface part of the inner surface 73 of the base 70, and a gap (especially the circumferential oil groove 79) is formed between the shaft head 31 and the second surface part of the inner surface 73 of the base 70. An oil discharge hole 36 is also formed in the lower part of the shaft head 31, which extends through the side wall of the rotating shaft 30 (that is, extends from the inner surface defining the oil hole 34 of the rotating shaft 30 to the outer surface of the rotating shaft 30) and is in fluid communication with the oil hole 34 and the circumferential oil groove 79. The oil discharge hole 36 can be substantially horizontal (that is, extending substantially in the radial direction) as shown in Figure 6b to facilitate oil discharge, but it can also be inclined relative to the horizontal direction (for example, inclined downward).

[0048] Thus, the oil discharge hole 36, the circumferential oil groove 79 and the oil discharge interface 76 together form the oil discharge channel DP of the oil circulation regulating mechanism. As shown in Figure 2 , the oil circulation regulating mechanism further includes an oil discharge valve 80. The oil discharge valve 80 is fixedly connected to the base 70 and is in fluid communication with the oil hole 34 in the rotating shaft 30 through the oil discharge channel DP. It should be noted that the "fixed connection" here means that there is no relative movement between the oil discharge valve 80 and the base 70 after the oil discharge valve 80 is connected to the base 70, rather than meaning that the oil discharge valve 80 cannot be disassembled from the base 70. The oil discharge valve 80 can be arranged such that its axis is generally perpendicular to the axis of the rotating shaft 30.

[0049] As shown in Figure 7 , Figure 8 and Figure 9 , the oil discharge valve 80 includes a generally cylindrical outer shell 82, a valve stopper 87 that can move axially along the oil discharge valve within the space surrounded by the outer shell 82, a plug-like member 83 for closing one end of the outer shell 82, and a spring 86 disposed between the plug-like member 83 and the valve stopper 87. The end 81 of the outer shell 82 opposite to the end provided with the plug-like member 83 is configured to have an inlet 84, and the outer contour of the end 81 is configured to be in a shape suitable for fixedly connecting to the oil discharge interface 76. The end 81 of the outer shell 82 can be configured to have a diameter smaller than the diameter of the remaining part of the outer shell 82 except the end 81, so as to form a stepped portion 88 between the end 81 and the remaining part of the outer shell 82 for defining the movement range of the valve stopper 87. One or more oil discharge holes 85 extending through the outer shell 82 (that is, extending from the inner surface of the outer shell 82 to the outer surface of the outer shell 82) are also formed in the remaining part of the outer shell 82, and the oil discharge holes 85 are located between the plug-like member 83 and the stepped portion 88.

[0050] As shown Figure 9 in the figure, the valve stopper 87 can be configured to include a central valve plate portion 871, a support leg portion 872 extending from the central valve plate portion 871 along a direction substantially perpendicular to the plane where the central valve plate portion 871 is located, and an annular portion 873 connecting the ends of the support leg portions 872 together. An opening is formed between adjacent support leg portions 872. This configuration of the valve stopper 87 not only facilitates the positioning connection between the spring 86 and the valve stopper 87, enabling the valve stopper 87 to move axially more smoothly within the housing 82, but also facilitates the lubricating oil to flow through the oil discharge valve 80 more sensitively and rapidly when the oil discharge valve 80 is opened.

[0051] The oil circulation regulation process of the compressor will be described below with reference to Figure 2 and Figure 8 . When the compressor is running, there is a certain pressure in the lubricating oil in the oil hole 34, and the rotation of the rotating shaft 30 also causes the lubricating oil to generate a centrifugal force, resulting in the lubricating oil flowing through the oil discharge hole 36, the circumferential oil groove 79, and the oil discharge interface 76 and entering the inlet 84 of the oil discharge valve 80, thereby applying pressure to the valve stopper 87. When the compressor is running at a low speed, the lubricating oil does not apply pressure to the valve stopper 87 or the pressure applied to the valve stopper 87 is small, that is, when the inlet 84 of the oil discharge valve 80 is not supplied with lubricating oil or the pressure of the supplied lubricating oil is less than the biasing force of the spring 86, the valve stopper 87 abuts against the step portion 88 under the action of the biasing force of the spring 86, thereby sealing and isolating the oil discharge hole 85 from the inlet 84. At this time, the oil discharge valve 80 is closed. When the compressor is running at a high speed, the pressure of the lubricating oil acting on the valve stopper 87 is large, that is, when the pressure of the lubricating oil supplied to the inlet 84 of the oil discharge valve 80 is greater than the biasing force of the spring 86, the valve stopper 87 overcomes the biasing force of the spring 86 and moves away from the step portion 88, enabling the inlet 84 to be in fluid communication with the oil discharge hole 85. The lubricating oil is discharged through the oil discharge hole 85 and flows back to the lubricating oil storage portion 18 (see the direction of the lubricating oil flow shown by the arrow in Figure 2 and 8 ). Thus, in the high-speed state of the compressor, the lubricating oil transported to the upper part of the compressor through the oil hole 34 of the rotating shaft 30 and thus entering the oil circulation is reduced, thereby reducing the oil circulation in the high-speed state of the compressor and avoiding excessive oil circulation in the high-speed state of the compressor, while not affecting the oil circulation in the low-speed state of the compressor.

[0052] Preferably, the oil circulation regulating mechanism further includes an oil supply pipe 93 fixedly connected to the base 70 to improve the oil circulation of the compressor in a low-speed state. It should be noted that the "fixed connection" here means that there is no relative movement between the oil supply pipe 93 and the base 70 after the oil supply pipe 93 is connected to the base 70, rather than meaning that the oil supply pipe 93 cannot be detached from the base 70. The base 70 also forms an oil supply interface 78 that extends through the base 70 (i.e., from the inner surface of the base 70 to the outer surface of the base 70) and is in fluid communication with the circumferential oil groove 79. Preferably, the oil supply interface 78 is provided in the area where the circumferential oil groove 79 is formed in the second surface portion, so as to facilitate fluid communication with the circumferential oil groove 79 and facilitate processing. As Figure 2 , Figure 10 shown, an oil supply joint 90 may also be provided at the oil supply interface 78. The oil supply joint 90 includes a first end 91 inserted into the oil supply interface 78 and a second end 92 opposite to the first end 91. The outer contour of the first end 91 is configured to be fixedly connected to the oil supply interface 78, preferably in a sealed fixed connection. The second end 92 is configured to be connected to the oil supply pipe 93, preferably in a detachable connection. Refer to Figure 1 . The first port 931 of the oil supply pipe 93 is connected to the second end 92 of the oil supply joint 78, and the second port 932 of the oil supply pipe 93 opposite to the first port 931 is disposed near the suction port 17 of the housing body 12.

[0053] The oil supply pipe 93 is in fluid communication with the oil hole 34 in the rotating shaft 30 through the oil drain hole 36, the circumferential oil groove 79, and the oil supply interface 78. That is to say, in this preferred embodiment, the oil drain passage DP not only includes the oil drain hole 36, the circumferential oil groove 79, and the oil drain interface 76, but also includes the oil supply interface 78. In addition, those skilled in the art can understand that although in this embodiment, the oil supply pipe 93 and the oil discharge valve 80 share a part of the lubricating oil flow path, that is, the oil drain hole 36 and the circumferential oil groove 79, which is beneficial to simplifying the structure and facilitating manufacturing and processing, it is also possible to respectively provide independent lubricating oil flow paths for the oil supply pipe 93 and the oil discharge valve 80, that is, to respectively provide two independent sets of oil drain passages to fluidly connect the oil supply pipe 93 with the oil hole 34 and to fluidly connect the oil discharge valve 80 with the oil hole 34.

[0054] Next, refer to Figure 2The additional oil circulation process of the compressor is described. In addition to the oil circulation regulation process of the compressor described above, since the compressor is additionally provided with an oil supply pipe 93, the lubricating oil can not only be delivered to the upper part of the compressor via the oil hole 34 of the rotating shaft 30, but also be additionally delivered to the upper part of the compressor through the oil supply pipe 93, and even delivered to a position near the suction port 17 of the compressor. Thus, the lubricating oil can lubricate components such as the compression mechanism, thrust surface, and cross slip ring under the entrainment of the refrigerant gas, thereby improving the oil circulation of the compressor especially when the compressor operates at a low speed. Therefore, the compressor described according to the preferred embodiment of the present invention including the oil supply pipe 93 can not only reduce the oil circulation of the compressor in the high-speed operation state, but also provide the oil circulation of the compressor in the low-speed operation state, so as to maintain the oil circulation of the compressor within a reasonable range, and is particularly suitable for the operation of a variable-frequency compressor.

[0055] It should be noted that the second port 932 of the oil supply pipe 93 is preferably arranged near the suction port 17 of the housing body 12, which is not only beneficial to the lubricating oil being entrained by the refrigerant gas to lubricate and cool various components of the compressor, but also the suction port 17 is usually arranged at the middle or upper-middle position of the housing body 12 in the axial direction. Thus, the second port 932 of the oil supply pipe 93 is also located at the middle or upper-middle position of the body 12 in the axial direction, so as to be higher than the base 70 located at the bottom of the housing body 12 and even higher than the oil drain valve 80 (especially the oil drain hole 85 of the oil drain valve 80). Therefore, in the high-speed operation state of the compressor, it is more difficult for the lubricating oil in the oil hole 34 of the rotating shaft 30 to be transported upward through the oil supply pipe 93 and discharged from the second port 932 of the oil supply pipe 93 compared with being discharged through the oil drain valve 80. In other words, in the high-speed operation state of the compressor, the oil discharge amount of the oil drain valve 80 is greater than the oil supply amount through the oil supply pipe 93 towards the suction port 17 of the compressor, thus ensuring the effect of reducing the oil circulation in the high-speed operation state of the compressor. On the other hand, those skilled in the art can understand that the second port 932 of the oil supply pipe 93 is not limited to being arranged near the suction port 17. The second port 932 of the oil supply pipe 93 can be arranged to be higher than the oil drain valve 80, which helps to reduce the influence of the oil supply pipe in the high-speed operation state of the compressor and achieve the effect of reducing the oil circulation in the high-speed operation state of the compressor.

[0056] Preferably, the oil supply interface 78 is arranged to be higher than the oil drain valve 80 (especially the oil drain hole 85 of the oil drain valve 80). Thus, in the high-speed operation state of the compressor, the lubricating oil in the oil hole 34 of the rotating shaft 30 can be discharged through the oil drain valve 80 first, so as to better avoid the oil supply pipe delivering too much lubricating oil to the upper part of the compressor and ensure the effect of reducing the oil circulation in the high-speed operation state of the compressor.

[0057] In order to reduce the influence of the oil supply pipe during the high-speed operation of the compressor and achieve the effect of reducing the oil circulation during the high-speed operation of the compressor, additionally or alternatively, the flow area of the oil supply pipe 93 can be set to be smaller than the flow area of the oil drain valve 80 (here, the flow area of the oil drain valve 80 can refer to the flow area of the inlet 84 of the housing 82). For example, the inner diameter of the oil supply pipe 93 is set to be smaller than the inner diameter of the oil drain valve 80 (here, the inner diameter of the oil supply pipe 93 can be uniform, and the inner diameter of the oil drain valve 80 can refer to the diameter of the inlet 84 of the housing 82). Additionally or alternatively, an adjustment nozzle can be provided at the second port 932 of the oil supply pipe 93 to adjust the flow rate in the oil supply pipe 93. For example, the flow rate in the oil supply pipe 93 is reduced during the high-speed operation of the compressor, and the flow rate of the oil supply pipe 93 is increased during the low-speed operation of the compressor. Thereby, not only can the oil circulation of the compressor under different rotational speed states be adjusted more effectively, but also a common specification oil supply pipe 93 can be used for different compressors, making manufacturing and installation more convenient. Additionally or alternatively, a separate on-off valve (not shown in the figure) can also be provided on the oil supply pipe 93, so as to selectively open and close the oil supply pipe 93 under different operating conditions of the compressor.

[0058] In addition, since the oil drain valve 80 and the oil supply pipe 93 are fixedly connected to the base 70 instead of a moving part such as a rotating shaft, the installation and operation are more stable and reliable. In particular, since the oil drain valve 80 is installed on the non-rotating base 70, the valve stopper 87 is not affected by the centrifugal force and is only affected by the pressure of the lubricating oil and the biasing force of the spring 86. As a result, the selection of the valve stopper 87 and the spring 86 is less restricted. That is, the valve stopper 87 can select a material of normal quality, and the spring 86 can select a spring with a smaller biasing force, without worrying that the oil drain valve will open at low speed due to the superposition of the centrifugal force of the valve stopper 87 itself, improving the reliability of the pressure relief valve and the formation control accuracy. At the same time, the spring with a smaller biasing force has a lower cost, occupies less space, and is more conducive to controlling the opening degree of the pressure relief valve.

[0059] In addition, although in the first embodiment of the present invention, the circumferential oil groove 79 is formed by at least partially recessing the second surface portion of the inner surface 73 of the base 70 towards the radially outer side, those skilled in the art can understand that the circumferential oil groove can also be formed by partially recessing the outer surface of the rotating shaft towards the radially inner side, or by jointly forming by partially recessing the inner surface of the base towards the radially outer side and partially recessing the outer surface of the rotating shaft towards the radially inner side, as long as the circumferential oil groove is formed between the base and the rotating shaft.

[0060] As in Figure 11 、 Figure 12a and Figure 12bIn the second embodiment of the present invention shown, the central through hole 71a of the base 70a is defined by the inner surface 73a of the base 70a. The inner surface 73a can be divided into a first surface portion 731a for mounting the bearing 72 (the upper portion in Figure 11 ), and a second surface portion 732a where the bearing 72 is not mounted (the lower portion in Figure 11 ). Among them, the first surface portion 731a is recessed toward the radially outer side compared with the second surface portion 732a for accommodating and mounting the bearing 72. The oil drain interface 76a and the oil supply interface 78a are preferably arranged in the area of the second surface portion 732a to facilitate fluid communication with the circumferential oil groove 79a and facilitate processing.

[0061] The second end of the rotating shaft 30a (the lower end in Figure 11 ) includes a shaft head 31a inserted and mounted into the base 70a. The shaft head 31a includes a first portion 311a (the upper portion in Figure 2 ) and a second portion 312a (the lower portion in Figure 2 ) in the axial direction. The outer surface of the second portion 312a is recessed toward the radially inner side relative to the outer surface of the first portion 311a, thereby forming a circumferential oil groove 79a. The first portion 311a is arranged to face the first surface portion 731a of the inner surface 73a of the base 70a, contact with the bearing 72 and form a support. The second portion 312a is arranged to face the second surface portion 732a of the inner surface 73a of the base 70a, and a gap (especially the circumferential oil groove 79) is formed between the second portion 312a and the second surface portion 732a of the inner surface 73a of the base 70a. A drain hole 36a is also formed in the second portion 312a of the shaft head 31a, which extends through the side wall of the rotating shaft 30a (that is, extends from the inner surface of the rotating shaft 30a defining the oil hole 34a to the outer surface of the rotating shaft 30a) and is in fluid communication with the oil hole 34a and the circumferential oil groove 79a. The drain hole 36a can be substantially horizontal (i.e., extending substantially in the radial direction) as shown in Figure 12b to facilitate oil drainage, but it can also be inclined relative to the horizontal direction (e.g., inclined downward).

[0062] In addition, although in the first and second embodiments of the present invention, the circumferential oil groove is configured to extend 360° circumferentially, those skilled in the art can understand that it is not limited thereto. The circumferential oil groove can extend less than 360° circumferentially (for example, extend 90°), so that the oil drain interface and the oil supply interface can be communicated via the circumferential oil groove, thereby ensuring that the oil drain interface and the oil supply interface can share the lubricating oil flow path from the oil hole of the rotating shaft to the oil drain interface and the oil supply interface, simplifying the structure, production and installation.

[0063] The accompanying drawings only show two exemplary embodiments under the concept of the present invention. Those skilled in the art can understand that the present invention is not limited to the above-described exemplary embodiments, but also includes variations or combinations of the above-described various examples. For example, the oil drain hole can be a single hole or more than one hole. The oil hole in the rotating shaft can be in fluid communication with the oil discharge interface and the oil supply interface through a single oil drain hole and a circumferential oil groove, or can be in fluid communication with the oil discharge interface and the oil supply interface through a plurality of oil drain holes without additionally designing a circumferential oil groove. In the technical solution with a single or multiple oil drain holes and omitting the circumferential oil groove, as the rotating shaft rotates, the oil drain hole intermittently aligns with the oil discharge interface or the oil supply interface, thereby achieving fluid communication between the oil drain hole and the oil discharge interface or the oil supply interface; or, the existing installation gap between the outer surface of the rotating shaft and the inner surface of the base is used as the circumferential oil groove, thereby achieving fluid communication between the oil drain hole and the oil discharge interface or the oil supply interface.

[0064] For another example, the oil drain hole, the oil discharge interface, the oil supply interface, and the oil drain hole can also be constructed in various shapes as needed, such as circular, oval, rectangular, and other suitable cross-sectional shapes. Preferably, the oil drain holes on the oil discharge valve are constructed as multiple holes and are arranged in the direction from the position adjacent to the step portion 88 towards the plug member 83, and / or are constructed as oval or rectangular holes, and their major axis / long side is arranged in the direction from the position adjacent to the step portion 88 towards the plug member 83, so that as the valve block moves away from the step portion 88 under the action of the lubricating oil pressure, the opening degree of the oil drain hole gradually increases, thereby achieving the purpose that the greater the rotational speed of the rotating shaft, the greater the oil discharge amount.

[0065] The above describes a rotary compressor according to a preferred embodiment of the present invention in conjunction with specific embodiments. It can be understood that the above description is only exemplary and not restrictive. Without departing from the scope of the present invention, those skilled in the art can think of various variations and modifications with reference to the above description. These variations and modifications are also included in the protection scope of the present invention.

Claims

1. A rotary compressor (100), comprising: A housing (10), the housing comprising a lubricating oil storage portion (18) for containing lubricating oil; Compression mechanism (20); a driving mechanism (DM) for driving the compression mechanism, the driving mechanism (DM) comprising a rotating shaft (30), the rotating shaft (30) being provided with an oil hole (34) extending in the axial direction of the rotating shaft, and the lubricating oil from the lubricating oil storage portion can be supplied to the oil hole; and a base (70) on which the rotating shaft is mounted, The rotary compressor is characterized in that the rotary compressor further comprises an oil unloading valve (80), the oil unloading valve is fixedly connected to the base, and the oil unloading valve is in fluid communication with the oil hole through an oil discharge passage (DP).

2. The rotary compressor according to claim 1, wherein: The oil discharge passage comprises: one or more oil discharge holes (36) extending through the side wall of the rotating shaft and in fluid communication with the oil hole, a circumferential oil groove (79, 79a) formed between the rotating shaft and the base and in fluid communication with the oil discharge holes, and an oil discharge interface (76) extending through the base and in fluid communication with the circumferential oil groove and the oil discharge valve; or The oil discharge passage includes: one or more oil discharge holes (36) extending through the side wall of the rotating shaft and in fluid communication with the oil hole, and an oil discharge interface (76) extending through the base and capable of fluid communication with the oil discharge holes and the oil discharge valve.

3. The rotary compressor according to claim 2, wherein: The circumferential oil groove (79a) is formed by partially recessing the outer surface of the rotating shaft toward the radial inside, and / or the circumferential oil groove (79) is formed by partially recessing the inner surface of the base toward the radial outside.

4. The rotary compressor according to claim 2, wherein: The oil unloading valve comprises a substantially cylindrical shell (82) and a valve stopper (87) capable of moving in the axial direction of the oil unloading valve within a space surrounded by the shell, one end of the oil unloading valve is configured to be closed, and the other end of the oil unloading valve is configured to have an inlet (84) and is connected to the oil unloading interface, and The housing (82) is provided with one or more oil discharge holes (85) extending through the housing.

5. The rotary compressor according to any one of claims 1 to 4, wherein: The rotary compressor further includes an oil supply pipe (93) fixedly connected to the base and in fluid communication with the oil hole through the oil discharge passage (DP).

6. The rotary compressor according to claim 5, wherein: The oil discharge passage comprises: one or more oil discharge holes (36) extending through the side wall of the rotating shaft and in fluid communication with the oil hole, a circumferential oil groove (79, 79a) formed between the rotating shaft and the base and in fluid communication with the oil discharge holes, an oil discharge interface (76) extending through the base and in fluid communication with the circumferential oil groove and the oil discharge valve, and an oil supply interface (78) extending through the base and in fluid communication with the circumferential oil groove and the oil supply pipe; or The oil drain passage comprises: one or more oil drain holes (36) extending through the side wall of the rotating shaft and in fluid communication with the oil hole, an oil discharge interface (76) extending through the base and capable of fluid communication with the oil drain holes and the oil discharge valve, and an oil supply interface (78) extending through the base and in fluid communication with the oil drain holes and the oil supply pipe.

7. The rotary compressor according to claim 5, wherein: A first port (931) of the oil supply pipe is connected to the base, and a second port (932) of the oil supply pipe opposite to the first port is higher than the oil unloading valve (80).

8. The rotary compressor according to claim 7, wherein: The housing is provided with an air inlet (17), and the second port (932) is arranged near the air inlet.

9. The rotary compressor according to claim 6, wherein: The oil supply interface (78) is higher than the oil unloading valve (80).

10. The rotary compressor according to claim 5, wherein: The flow area of ​​the oil supply pipe is smaller than the flow area of ​​the oil unloading valve.

11. The rotary compressor according to claim 5, wherein: The first port (931) of the oil supply pipe is connected to the base, and a regulating nozzle is provided at a second port (932) of the oil supply pipe opposite to the first port to regulate the flow in the oil supply pipe.

12. The rotary compressor according to claim 5, wherein: The oil supply pipe is provided with a separate opening and closing valve.

13. The rotary compressor according to claim 6, wherein: The circumferential oil groove extends 360° in the circumferential direction, or The circumferential oil groove extends less than 360° in the circumferential direction, so that the oil unloading interface and the oil drain interface can be communicated via the circumferential oil groove.

14. The rotary compressor according to any one of claims 1 to 4, wherein: The rotary compressor is a variable frequency scroll compressor.

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