Compression assembly for rotary compressor and rotary compressor

Abstract

The invention discloses a compression assembly for a rotary compressor and the rotary compressor, and relates to the technical field of compressors. The compression assembly comprises a motor, an upper air cylinder, a lower air cylinder, a crankshaft and a balance part. Each of the upper cylinder and the lower cylinder is provided with a compression cavity and an exhaust hole communicated with the compression cavity and the outside; the crankshaft comprises a crankshaft body, a first eccentric part and a second eccentric part, the first eccentric part and the second eccentric part are arranged in the axial direction of the crankshaft body at intervals, and the electronic rotor is in driving connection with the crankshaft body so that the first eccentric part can drive the piston to eccentrically rotate in the compression cavity of the upper air cylinder and the second eccentric part can drive the piston to eccentrically rotate in the compression cavity of the lower air cylinder. The balance piece is connected with the rotor and used for offsetting eccentric loads generated by rotation of the first eccentric part and the second eccentric part; the upper air cylinder and the lower air cylinder are different in height, and the exhaust hole of the higher air cylinder is larger than the exhaust hole of the other air cylinder. According to the technical scheme, the problem that the performance of the compressor becomes poor due to the fact that a balance block is arranged in an existing rotary compressor can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of compressors, and in particular to a compression assembly for a rotary compressor and a rotary compressor. Background Art

[0002] Existing rotary compressors mainly use eccentric rollers to compress gas, and the structure of the eccentric roller will inevitably produce eccentric loads, especially when running at high speeds, the eccentric load will be aggravated. Therefore, it is usually necessary to add balancing blocks on the upper and lower parts of the motor to offset the unbalanced force and unbalanced torque caused by the eccentric roller, so as to achieve force and torque balance.

[0003] However, the use of balancing blocks not only increases the processing and installation materials, but also increases the requirements for motor production and installation. Installation errors will cause the consistency of compressor vibration and noise to deteriorate. In addition, the balancing blocks will also lead to additional increases in wind resistance and oil churning losses. Summary of the invention

[0004] The main purpose of the present invention is to provide a compression assembly for a rotary compressor, aiming to solve the problem that the setting of a balancing block in the existing rotary compressor leads to poor compressor performance.

[0005] To achieve the above object, the present invention provides a compression assembly for a rotary compressor, comprising:

[0006] A motor, the motor comprising a rotor;

[0007] An upper cylinder and a lower cylinder, wherein the upper cylinder is disposed between the motor and the lower cylinder, and each of the upper cylinder and the lower cylinder has a compression chamber and an exhaust hole connecting the compression chamber and the outside;

[0008] A crankshaft, the crankshaft comprising a crankshaft body and a first eccentric portion and a second eccentric portion spaced apart along the axial direction of the crankshaft body, the first eccentric portion and the second eccentric portion both being sleeved with pistons on their outer circumferences, the rotor being drivingly connected to the crankshaft body so that the first eccentric portion drives the piston to eccentrically rotate in the compression chamber of the upper cylinder, and the second eccentric portion drives the piston to eccentrically rotate in the compression chamber of the lower cylinder; and

[0009] a balancing member connected to the rotor and disposed on a side of the motor close to and / or away from the upper cylinder, the balancing member being used to offset the eccentric load generated by the rotation of the first eccentric portion and the second eccentric portion;

[0010] Wherein, in the axial direction of the crankshaft body, the upper cylinder and the lower cylinder have different heights, and the exhaust hole of the higher one is larger than the exhaust hole of the other one.

[0011] In one embodiment, the mass of the first eccentric portion is greater than the mass of the second eccentric portion, and the second eccentric portion and the balance member are located on the same side of the crankshaft body.

[0012] In one embodiment, in the axial direction of the crankshaft body, the height of the first eccentric portion is greater than the height of the second eccentric portion.

[0013] In one embodiment, in the axial direction of the crankshaft body, the height of the upper cylinder is greater than the height of the lower cylinder.

[0014] In one embodiment, the exhaust pressure of the lower cylinder is greater than the exhaust pressure of the upper cylinder.

[0015] In one embodiment, the upper cylinder is for medium-pressure exhaust, and the lower cylinder is for high-pressure exhaust.

[0016] In one embodiment, the balancing member includes a balancing block, and the balancing block is arranged on a side of the motor close to or away from the upper cylinder.

[0017] In one embodiment, the compressor is a vertical compressor, and the balancing block is arranged on a side of the motor away from the upper cylinder.

[0018] In one embodiment, the eccentricity of the first eccentric portion is greater than the eccentricity of the second eccentric portion.

[0019] The present invention further provides a rotary compressor, comprising a shell and the compression assembly as described above, wherein the compression assembly is arranged in the shell.

[0020] The technical solution of the present invention is to arrange the first eccentric part and the second eccentric part at intervals in the axial direction of the crankshaft body, so that when the rotor of the motor drives the crankshaft body to rotate, the first eccentric part can drive the piston to rotate eccentrically in the compression chamber of the upper cylinder, and the second eccentric part can drive the piston to rotate eccentrically in the compression chamber of the lower cylinder. The upper cylinder and the lower cylinder are two independent cylinders. The height of the upper cylinder and / or the lower cylinder in the axial direction of the crankshaft body is reduced so that the height of the upper cylinder and / or the lower cylinder is different. On the one hand, the height of the cylinder affects the volume of the compression chamber. The compression chamber volume of the cylinder with a higher height is larger. Accordingly, setting its exhaust hole larger can reduce its exhaust resistance, avoid leakage of the working fluid in the compression chamber, and improve the reliability and stability of the compressor operation. On the other hand, after the cylinder height is reduced, the force arm of the unbalanced torque of the first eccentric part and / or the second eccentric part on the crankshaft body is reduced, and the unbalanced torque generated accordingly is reduced, that is, the eccentric load generated by the rotation of the first eccentric part and the second eccentric part is reduced. When a balancing part connected to the rotor is set to offset the eccentric load generated by the rotation of the first eccentric part and the second eccentric part, the number and mass of the balancing part can be reduced, the wind resistance and oil stirring loss caused by setting the balancing part can be reduced, and the overall performance of the compressor can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of an embodiment of a compression assembly for a rotary compressor of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the structure behind the motor hidden in the middle compression assembly;

[0024] Figure 3 for Figure 1 Schematic diagram of the structure of the middle compression assembly after the cylinder and motor are hidden;

[0025] Figure 4 for Figure 1 A top view of the middle compression assembly;

[0026] Figure 5 for Figure 3 Top view of the compression assembly.

[0027] Description of Figure Numbers:

[0028] Label name Label name 10 Compression components 100 Motor 200 Upper cylinder 300 Lower cylinder 400 Crankshaft 410 Crankshaft body 420 The first eccentric part 430 Second eccentric part 500 Balance parts 600 End Plate

[0029] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] Existing rotary compressors mainly use eccentric rollers to compress gas, and the structural form of the eccentric roller will inevitably produce eccentric loads, especially when running at high speeds, the eccentric load will be aggravated. Therefore, it is usually necessary to add balancing blocks to the upper and lower parts of the motor to offset the unbalanced force and unbalanced torque caused by the eccentric roller, so as to achieve force and torque balance. However, the use of balancing blocks not only increases the processing and installation materials, but also increases the requirements for motor production and installation. Installation errors will cause the consistency of compressor vibration and noise to deteriorate; in addition, the balancing blocks will also increase wind resistance and oil stirring losses.

[0034] In order to solve the above problems, the present invention provides a compression assembly for a rotary compressor.

[0035] See also Figures 1 to 5In this embodiment, the compression assembly 10 includes a motor 100, an upper cylinder 200, a lower cylinder 300, a crankshaft 400 and a balance member 500; wherein the motor 100 includes a rotor; the upper cylinder 200 is arranged between the motor 100 and the lower cylinder 300, and the upper cylinder 200 and the lower cylinder 300 both have a compression chamber and an exhaust hole connecting the compression chamber and the outside; the crankshaft 400 includes a crankshaft body 410 and a first eccentric portion 420 and a second eccentric portion 430 spaced apart along the axial direction of the crankshaft body 410, the outer circumferences of the first eccentric portion 420 and the second eccentric portion 430 are both sleeved with pistons, and the rotor drives the crankshaft body 410 to connect the first eccentric portion 420 and the second eccentric portion 430. The shaft body 410 is configured to enable the first eccentric portion 420 to drive the piston to rotate eccentrically in the compression chamber of the upper cylinder 200, and enable the second eccentric portion 430 to drive the piston to rotate eccentrically in the compression chamber of the lower cylinder 300; the balancing member 500 is connected to the rotor and is arranged on a side of the motor 100 close to and / or away from the upper cylinder 200, and the balancing member 500 is used to offset the eccentric load generated by the rotation of the first eccentric portion 420 and the second eccentric portion 430; the upper cylinder 200 and the lower cylinder 300 have different heights in the axial direction of the crankshaft body 410, and the exhaust hole of the one with the higher height is larger than the exhaust hole of the other.

[0036] By arranging the first eccentric portion 420 and the second eccentric portion 430 in the axial direction of the crankshaft body 410 at intervals, when the rotor of the motor 100 drives the crankshaft body 410 to rotate, the first eccentric portion 420 can drive the piston to rotate eccentrically in the compression chamber of the upper cylinder 200, and the second eccentric portion 430 can drive the piston to rotate eccentrically in the compression chamber of the lower cylinder 300. The upper cylinder 200 and the lower cylinder 300 are two independent cylinders. By reducing the height of the upper cylinder 200 and / or the lower cylinder 300 in the axial direction of the crankshaft body 410, the heights of the upper cylinder 200 and the lower cylinder 300 are different. On the one hand, the height of the cylinder affects the volume of the compression chamber. The compression chamber volume of the cylinder with a higher height is larger. Accordingly, setting its exhaust hole larger can reduce its exhaust resistance, avoid leakage of the working medium in the compression chamber, and improve the reliability and stability of the compressor operation. On the other hand, after the cylinder height is reduced, the first The lever arm of the unbalanced torque of the eccentric portion 420 and / or the second eccentric portion 430 on the crankshaft body 410 is reduced, and the unbalanced torque generated accordingly is reduced, that is, the eccentric load generated by the rotation of the first eccentric portion 420 and the second eccentric portion 430 is reduced. When a balancing member 500 connected to the rotor is provided to offset the eccentric load generated by the rotation of the first eccentric portion 420 and the second eccentric portion 430, the number and mass of the balancing member 500 can be reduced, and the wind resistance and oil stirring loss caused by the provision of the balancing member 500 can be reduced, thereby improving the overall performance of the compressor.

[0037] Taking the example of an existing compressor in which an upper balancing block is provided on one side of the motor 100 and a lower balancing block is provided on the other side, the force balance relationship between the upper balancing block and the lower balancing block satisfies:

[0038] ∑F=F1-F2-F3+F4=0

[0039] Wherein, F1 is the unbalanced force of the first eccentric part 420, -F2 is the unbalanced force of the second eccentric part 430, -F3 is the centrifugal force of the upper balancing block, and F4 is the centrifugal force of the lower balancing block;

[0040] The torque balance relationship between the upper balancing block and the lower balancing block satisfies:

[0041] ∑M=M1-M2-M3+M4+M5=0

[0042] Among them, M1 is the unbalanced moment of the first eccentric part 420, -M2 is the unbalanced moment of the second eccentric part 430, -M3 is the gravity moment of the upper balancing block, M4 is the gravity moment of the lower balancing block, and M5 is the additional moment generated by the deflection of the crankshaft body 410.

[0043] The unbalanced force and the unbalanced moment of the first eccentric part 420 are related to the mass of the first eccentric part 420, and the unbalanced force and the unbalanced moment of the second eccentric part 430 are related to the mass of the second eccentric part 430. By changing the mass of the first eccentric part 420 and the second eccentric part 430, balancing blocks of different masses and quantities can be used to satisfy the above-mentioned force balance and moment balance.

[0044] In view of this, in one embodiment, the mass of the first eccentric portion 420 is greater than the mass of the second eccentric portion 430, and the second eccentric portion 430 and the balance member 500 are located on the same side of the crankshaft body 410. Generally, in the existing compressor, the mass of the first eccentric portion 420 and the second eccentric portion 430 are the same. Specifically, to achieve that the mass of the first eccentric portion 420 is greater than the mass of the second eccentric portion 430, it can be achieved by maintaining the mass of the first eccentric portion 420 unchanged and reducing the mass of the second eccentric portion 430; it can also be achieved by maintaining the mass of the second eccentric portion 430 unchanged and increasing the mass of the first eccentric portion 420; it can also be achieved by increasing the mass of the first eccentric portion 420 and reducing the mass of the second eccentric portion 430.

[0045] It can be understood that when the mass of the first eccentric portion 420 is greater than that of the second eccentric portion 430, it is only necessary to arrange the balance member 500 and the second eccentric portion 430 on the same side of the crankshaft body 410, so that a single balance member 500 can offset the eccentric load generated by the rotation of the first eccentric portion 420 and the second eccentric portion 430, and by reducing the number of the balance members 500, the wind resistance and oil stirring loss caused by the setting of the balance members 500 can be reduced. At the same time, the masses of the first eccentric portion 420 and the second eccentric portion 430 can continue to be controlled to adjust the mass and volume of the balancing member 500. Specifically, the balancing member 500 can be set by lowering the height of the balancing member 500, reducing the volume of the balancing member 500, or reducing the cross-sectional area of ​​the balancing member 500. By lowering the height of the balancing member 500, the overall height of the compressor can be reduced, the performance of the compressor can be improved, and the cost of the compressor can be reduced; by reducing the volume of the balancing member 500, the centrifugal force generated by the balancing member 500 during the operation of the compression assembly 10 can be reduced; and by reducing the cross-sectional area of ​​the balance block, the wind resistance during the operation of the compression assembly 10 can be reduced, and the disturbance to the exhaust gas can be reduced.

[0046] In one embodiment, the height of the first eccentric portion 420 is set to be greater than the height of the second eccentric portion 430 in the axial direction of the crankshaft body 410, so that the mass of the first eccentric portion 420 is greater than the mass of the second eccentric portion 430. Accordingly, in order to avoid leakage of the working medium in the compression chamber, the heights of the upper cylinder 200 and the lower cylinder 300 are adjusted accordingly, so that in the axial direction of the crankshaft body 410, the height of the upper cylinder 200 is greater than the height of the lower cylinder 300.

[0047] Specifically, in order to achieve that the height of the first eccentric portion 420 is greater than the height of the second eccentric portion 430, and the height of the upper cylinder 200 is greater than the height of the lower cylinder 300, the height of the first eccentric portion 420 and the height of the upper cylinder 200 can be maintained unchanged while the height of the second eccentric portion 430 and the height of the lower cylinder 300 are reduced; or the height of the first eccentric portion 420 and the upper cylinder 200 can be increased while the height of the second eccentric portion 430 and the lower cylinder 300 are maintained unchanged; or the height of the first eccentric portion 420 and the upper cylinder 200 can be increased while the height of the second eccentric portion 430 and the lower cylinder 300 are reduced.

[0048] As can be seen from the above, after the height of the upper cylinder 200 and / or the lower cylinder 300 changes, the volume of the compression chamber thereof also changes. When the height of the upper cylinder 200 is greater than the height of the lower cylinder 300, by setting the exhaust hole of the upper cylinder 200 to be larger than the exhaust hole of the lower cylinder 300, the smooth exhaust inside the compressor can be maintained. In order to further reduce the impact of the volume change of the compression chamber on the exhaust of the upper cylinder 200 and the lower cylinder 300, the exhaust pressure of the lower cylinder 300 is set to be greater than the exhaust pressure of the upper cylinder 200. Preferably, the upper cylinder 200 is medium-pressure exhaust, and the lower cylinder 300 is high-pressure exhaust.

[0049] It is understandable that the mass of the first eccentric part 420 can be greater than the mass of the second eccentric part 430 in many other ways. For example, the eccentricity of the first eccentric part 420 is set to be greater than the eccentricity of the second eccentric part 430, or the second eccentric part 430 is set to be partially hollow. At the same time, considering that the unbalanced force and unbalanced moment of the first eccentric part 420 and the second eccentric part 430 are also affected by the eccentricity of the first eccentric part 420 and the second eccentric part 430, in order to adjust the eccentric load generated by the rotation of the first eccentric part 420 and the second eccentric part 430, in addition to changing the mass of the first eccentric part 420 and / or the second eccentric part 430, the eccentricity of the first eccentric part 420 and / or the second eccentric part 430 can also be adjusted, and the eccentricity can also be adjusted at the same time when the mass of the first eccentric part 420 and / or the second eccentric part 430 is adjusted.

[0050] See also Figure 1 and Figure 2 In one embodiment, the balancing member 500 includes a balancing block, and the balancing block is arranged on the side of the motor 100 close to or away from the upper cylinder 200. Compared with the existing compressor in which balancing blocks are arranged on both sides of the motor 100, in this embodiment, the balancing block is only arranged on the side of the motor 100 close to or away from the upper cylinder 200, which reduces the material cost of the compression assembly 10, optimizes the structural space inside the compressor, and can reduce the adverse effects caused by installing the balancing block. The compressor can be a horizontal compressor or a vertical compressor. Preferably, when the compressor is a vertical compressor, the balancing member 500 includes a balancing block, and the balancing block is arranged on the side of the motor 100 away from the upper cylinder 200, that is, the balancing block between the motor 100 and the upper cylinder 200 is eliminated, which can reduce the distance between the motor 100 and the upper cylinder 200, reduce the disturbance of the crankshaft body 410, and can also reduce the height of the oil from the motor 100 to the bottom of the compressor.

[0051] Specifically, the rotor is sleeved on the crankshaft body 410, and the crankshaft body 410 is also sleeved with an end plate 600, the end plate 600 is connected to the rotor, and the balancing block is fixed to the rotor through the end plate 600. The balancing piece 500 can be integrally formed with the end plate 600, and the end plate 600 can be fixedly connected to the rotor by bolt connection, welding, bonding or clamping.

[0052] The present invention further provides a rotary compressor, which includes a housing and the compression assembly 10 as described above, wherein the compression assembly 10 is disposed in the housing. Since the rotary compressor of the present invention adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0053] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A compression assembly for a rotary compressor, characterized in that: include: A motor, the motor comprising a rotor; An upper cylinder and a lower cylinder, wherein the upper cylinder is disposed between the motor and the lower cylinder, and each of the upper cylinder and the lower cylinder has a compression chamber and an exhaust hole connecting the compression chamber and the outside; A crankshaft, the crankshaft comprising a crankshaft body and a first eccentric portion and a second eccentric portion spaced apart in an axial direction of the crankshaft body, the first eccentric portion and the second eccentric portion being sleeved with a piston on their outer circumferences, the rotor being drivingly connected to the crankshaft body so that the first eccentric portion drives the piston to rotate eccentrically in the compression chamber of the upper cylinder, and the second eccentric portion drives the piston to rotate eccentrically in the compression chamber of the lower cylinder; as well as a balancing member connected to the rotor and disposed on a side of the motor close to and / or away from the upper cylinder, the balancing member being used to offset the eccentric load generated by the rotation of the first eccentric portion and the second eccentric portion; Wherein, in the axial direction of the crankshaft body, the upper cylinder and the lower cylinder have different heights, and the exhaust hole of the higher one is larger than the exhaust hole of the other one.

2. The compression assembly for a rotary compressor according to claim 1, characterized in that: The mass of the first eccentric portion is greater than the mass of the second eccentric portion, and the second eccentric portion and the balance member are located on the same side of the crankshaft body.

3. The compression assembly for a rotary compressor according to claim 2, characterized in that: In the axial direction of the crankshaft body, the height of the first eccentric portion is greater than the height of the second eccentric portion.

4. The compression assembly for a rotary compressor according to claim 3, characterized in that: In the axial direction of the crankshaft body, the height of the upper cylinder is greater than the height of the lower cylinder.

5. The compression assembly for a rotary compressor according to claim 4, characterized in that: The exhaust pressure of the lower cylinder is greater than the exhaust pressure of the upper cylinder.

6. The compression assembly for a rotary compressor according to claim 5, characterized in that: The upper cylinder is for medium-pressure exhaust, and the lower cylinder is for high-pressure exhaust.

7. The compression assembly for a rotary compressor according to any one of claims 2 to 6, characterized in that: The balancing member includes a balancing block, and the balancing block is arranged on a side of the motor close to or far away from the upper cylinder.

8. The compression assembly for a rotary compressor according to claim 7, characterized in that: The compressor is a vertical compressor, and the balancing block is arranged on a side of the motor away from the upper cylinder.

9. The compression assembly for a rotary compressor according to claim 2, characterized in that: The eccentricity of the first eccentric portion is greater than the eccentricity of the second eccentric portion.

10. A rotary compressor, characterized in that: It comprises a shell and a compression assembly as claimed in any one of claims 1 to 9, wherein the compression assembly is arranged in the shell.

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