A screw compressor and air conditioner

Abstract

The utility model provides a kind of screw compressor and air conditioner, screw compressor includes multiple rotor pairs, each rotor pair is sequentially arranged two-stage first rotor pair, two-stage second rotor pair, one-stage first rotor pair, one-stage second rotor pair, two-stage third rotor pair and two-stage fourth rotor pair;Two-stage first rotor pair and two-stage second rotor pair are symmetrically arranged, one-stage first rotor pair and one-stage second rotor pair are symmetrically arranged, two-stage third rotor pair and two-stage fourth rotor pair are symmetrically arranged;Each rotor pair is inhaled from the side of respective meshing position, and exhaust from the other side of respective meshing position;And the suction side of one-stage first rotor pair and one-stage second rotor pair is opposite to the suction side of two-stage first rotor pair, two-stage second rotor pair, two-stage third rotor pair and two-stage fourth rotor pair four.The technical scheme of the utility model can balance the axial gas force of rotor while improving the balance of radial gas force of rotor.

Description

Technical Field

[0001] This utility model belongs to the field of compressor technology, specifically relating to a screw compressor and an air conditioner. Background Technology

[0002] When an oil-injected screw compressor compresses a medium gas, the compressor rotor itself is simultaneously subjected to the reaction force of the medium gas. When analyzing the gas forces acting on the rotor, the resultant gas force is typically decomposed into axial and radial gas forces, and then corresponding load-bearing structures and solutions are designed. Generally, the bearings are the final carriers of the axial and radial gas forces. The lifespan of the bearings directly affects the service life of the screw compressor. Overloading a single bearing can lead to a precipitous drop in its lifespan. Rolling bearings also have a minimum load requirement to ensure that the rolling elements rotate properly rather than slip; otherwise, the bearing will also be damaged. Therefore, after determining the forces acting on the rotor, the bearing type and quantity are selected based on the values ​​of the axial and radial gas forces to avoid bearing overload. Under some harsh operating conditions, due to the large rotor gas forces, the selected bearing size and number may be increased. However, when the operating conditions change, the rotor gas forces may decrease significantly for a period of time, even falling below the minimum load required by the bearings, causing bearing damage. Furthermore, increasing the size and number of bearings is also detrimental to the size, weight, and cost of the compressor.

[0003] The optimal solution for bearing load distribution is to counteract the rotor gas force at its source. Existing related technologies employ two pairs of rotors of identical size but opposite directions. During operation, regardless of the magnitude of the gas force, the axial gas force is always canceled out and balanced, resulting in a small and stable axial gas force. This requires only a single small-load bearing, simplifying the structure, improving reliability, and reducing costs. However, the radial gas force is not completely counteracted, and the radial gas force still presents problems of large loads and large variations. Utility Model Content

[0004] Therefore, this utility model provides a screw compressor and an air conditioner, and the main technical problem to be solved is: how to improve the balance of radial gas force of the rotor while ensuring the balance of axial gas force of the rotor.

[0005] To solve the above problems, this utility model provides a screw compressor, which includes multiple rotor pairs, each rotor pair having a pair of meshing male rotor and female rotor, the male rotors of each rotor pair being coaxially arranged, and the female rotors of each rotor pair being coaxially arranged.

[0006] The rotor pairs are respectively a second-stage first rotor pair, a second-stage second rotor pair, a first-stage first rotor pair, a second-stage second rotor pair, a second-stage third rotor pair, and a second-stage fourth rotor pair; the second-stage first rotor pair and the second-stage second rotor pair are symmetrically arranged, the first-stage first rotor pair and the second-stage second rotor pair are symmetrically arranged, and the second-stage third rotor pair and the second-stage fourth rotor pair are symmetrically arranged.

[0007] Each of the rotor pairs draws air from one side of its respective meshing position and exhausts air from the other side of its respective meshing position; and the air intake sides of the first-stage rotor pair and the second-stage rotor pair are opposite to the air intake sides of the first-stage rotor pair, the second-stage rotor pair, the third-stage rotor pair, and the fourth-stage rotor pair.

[0008] In some embodiments, the resultant radial force on both the first-stage first rotor pair and the second-stage first rotor pair is F. 合1 The resultant radial force on the first secondary rotor pair, the second secondary rotor pair, the third secondary rotor pair, and the fourth secondary rotor pair is F. 合2 ;

[0009] Among them, F 合1 With F 合2 The two are equal in size and opposite in direction.

[0010] In some embodiments, the second-stage first rotor pair and the second-stage fourth rotor pair are symmetrically arranged; and the radial resultant force on the male rotor of the first-stage first rotor pair is F1, the radial resultant force on the female rotor of the first-stage first rotor pair is F2, the radial resultant force on the male rotor of the second-stage first rotor pair is F4, and the radial resultant force on the female rotor of the second-stage first rotor pair is F3.

[0011] Among them, F1 and F3 are in opposite directions, and F1 = 2 * F3; F2 and F4 are in opposite directions, and F2 = 2 * F4.

[0012] In some embodiments, the end face profiles of each rotor in the first-stage first rotor pair and the first-stage second rotor pair are consistent and are all first end face profiles; the end face profiles of each rotor in the second-stage first rotor pair, the second-stage second rotor pair, the third-stage second rotor pair, and the fourth-stage second rotor pair are consistent and are all second end face profiles.

[0013] The first end face profile and the second end face profile are scaled proportionally.

[0014] In some embodiments, the intake sides of the second-stage first rotor pair, the second-stage second rotor pair, the third-stage second rotor pair, and the fourth-stage second rotor pair are all used to draw air from the exhaust sides of both the first-stage first rotor pair and the second-stage first rotor pair.

[0015] In some embodiments, the second-stage first rotor pair, the second-stage second rotor pair, the first-stage first rotor pair, the first-stage second rotor pair, the second-stage third rotor pair, and the second-stage fourth rotor pair are arranged sequentially along a first direction, which is the axial direction of the shaft where the male rotor of each rotor pair is located.

[0016] In some embodiments, the screw compressor further includes a housing having a separated first compression chamber, a second compression chamber, and a third compression chamber; the second-stage first rotor pair and the second-stage second rotor pair are both disposed in the first compression chamber, the first-stage first rotor pair and the second-stage second rotor pair are both disposed in the second compression chamber, and the second-stage third rotor pair and the second-stage fourth rotor pair are both disposed in the third compression chamber.

[0017] The machine body has a first flow channel inside, which has a first air outlet, a second air outlet, a third air outlet, a fourth air outlet, and a fifth air outlet. The first air outlet and the second air outlet are both connected to the first compression chamber. The intake side of the second-stage first rotor pair draws air through the first air outlet, and the intake side of the second-stage second rotor pair draws air through the second air outlet. The third air outlet and the fourth air outlet are both connected to the third compression chamber. The intake side of the second-stage third rotor pair draws air through the third air outlet, and the intake side of the second-stage fourth rotor pair draws air through the fourth air outlet. The fifth air outlet is connected to the second compression chamber, and the exhaust sides of both the first-stage first rotor pair and the second-stage second rotor pair exhaust through the fifth air outlet.

[0018] In some implementations, the first flow channel is symmetrically arranged about the midpoint of the first stage first rotor pair and the second stage second rotor pair.

[0019] In some embodiments, when the screw compressor includes a housing, and the housing has a separated first compression chamber, a second compression chamber, and a third compression chamber; the second-stage first rotor pair and the second-stage second rotor pair are both disposed in the first compression chamber, the first-stage first rotor pair and the second-stage second rotor pair are both disposed in the second compression chamber, and the second-stage third rotor pair and the second-stage fourth rotor pair are both disposed in the third compression chamber,

[0020] The first compression chamber has a first exhaust port, and the exhaust sides of both the second-stage first rotor pair and the second-stage second rotor pair exhaust through the first exhaust port. The third compression chamber has a second exhaust port, and the exhaust sides of both the second-stage third rotor pair and the second-stage fourth rotor pair exhaust through the second exhaust port. The first exhaust port and the second exhaust port are symmetrically arranged about the midpoint of the first-stage first rotor pair and the first-stage second rotor pair.

[0021] And / or, the machine body has a second flow channel, the second flow channel having a second A air outlet, a second B air outlet and a second C air outlet, the second B air outlet and the second C air outlet are both connected to the second compression chamber, and the intake side of the first stage first rotor pair draws air through the second B air outlet, the intake side of the first stage second rotor pair draws air through the second C air outlet, and the second A air outlet penetrates the outer wall of the machine body; the second flow channel is symmetrically arranged about the midpoint of the first stage first rotor pair and the first stage second rotor pair.

[0022] In some embodiments, a first bearing is fitted on the shaft segment between the male rotors of the second secondary rotor pair and the first primary rotor pair, and a second bearing is fitted on the shaft segment between the female rotors of the two pairs; a third bearing is fitted on the shaft segment between the male rotors of the third secondary rotor pair and the first primary rotor pair, and a fourth bearing is fitted on the shaft segment between the female rotors of the two pairs.

[0023] And / or, each of the male rotor shafts of each rotor pair is provided with a fifth bearing at both ends, and each of the female rotor shafts of each rotor pair is provided with a sixth bearing at both ends.

[0024] This utility model also provides an air conditioner, which may include the screw compressor described in any one of the above-mentioned methods.

[0025] The screw compressor and air conditioner provided by this utility model have the following beneficial effects:

[0026] 1. This utility model improves the rotor radial gas force balance of the screw compressor by making the intake sides of the first and second primary rotor pairs opposite to the intake sides of the second, third, and fourth secondary rotor pairs, and the exhaust sides of the first and second primary rotor pairs also opposite to the exhaust sides of the second, third, and fourth secondary rotor pairs. This results in the radial gas force on the first and second primary rotor pairs being opposite in direction to the radial gas force on the second, third, and fourth secondary rotor pairs.

[0027] 2. The technical solution of this utility model can balance all the gas forces, so that the theoretical gas resultant force of the entire compressor is zero, and the bearing can be truly reduced to near zero load (only needing to bear the weight of the parts, the impact of transportation and operation, and mechanical positioning), which greatly improves the service life of the bearing.

[0028] 3. Because the load is largely balanced, the mechanical vibration of the screw compressor of this invention is also greatly reduced, thus lowering the noise caused by the compressor's mechanical and airflow pulsations. Attached Figure Description

[0029] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the rotor structure of a screw compressor provided in one embodiment of the present invention;

[0031] Figure 2 This is a cross-sectional view of a screw compressor provided in one embodiment of the present invention;

[0032] Figure 3 yes Figure 2 Sectional view along the middle AA direction;

[0033] Figure 4 yes Figure 2 Sectional view along the BB direction;

[0034] Figure 5This is a schematic diagram of the radial gas forces on each rotor of a screw compressor provided in one embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the rotor structure and bearing assembly of a screw compressor according to an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the rotor structure and bearing assembly of another screw compressor provided in one embodiment of the present invention.

[0037] The attached figures are labeled as follows:

[0038] 1. First stage first rotor pair; 2. First stage second rotor pair; 3. First flow channel; 4. Machine body; 5. Second flow channel; 6. First bearing; 7. Second bearing; 8. Third bearing; 9. Fourth bearing; 10a. Fifth bearing; 10b. Sixth bearing; 11. Second stage first rotor pair; 12. Second stage second rotor pair; 13. First shaft; 14. Second shaft; 21. Second stage third rotor pair; 22. Second stage fourth rotor pair; 31. First air outlet; 32. Second air outlet; 33. Third air outlet; 34. Fourth air outlet; 35. Fifth air outlet; 41. First compression chamber; 42. Second compression chamber; 43. Third compression chamber; 401. First exhaust port; 403. Second exhaust port; 501. Second A air outlet; 502. Second B air outlet; 503. Second C air outlet; a. Split surface. Detailed Implementation

[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0040] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0041] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0042] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0043] See also Figure 1-7 As shown, according to an embodiment of the present invention, a screw compressor is provided, comprising multiple rotor pairs, each rotor pair having a pair of meshing male and female rotors. The male rotors of each rotor pair are coaxially arranged, for example, all mounted on a first rotating shaft 13. The female rotors of each rotor pair are also coaxially arranged, for example, all mounted on a second rotating shaft 14. The first rotating shaft 13 and the second rotating shaft 14 are parallel.

[0044] The rotor pairs are: secondary first rotor pair 11, secondary second rotor pair 12, primary first rotor pair 1, primary second rotor pair 2, secondary third rotor pair 21, and secondary fourth rotor pair 22. Secondary first rotor pair 11 and secondary second rotor pair 12 are symmetrically arranged, primary first rotor pair 1 and primary second rotor pair 2 are symmetrically arranged, and secondary third rotor pair 21 and secondary fourth rotor pair 22 are symmetrically arranged.

[0045] Each of the aforementioned rotor pairs draws air from one side of its respective meshing position and exhausts air from the other side. Furthermore, the intake sides of the first-stage rotor pair 1 and the second-stage rotor pair 2 are opposite to those of the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22. Correspondingly, the exhaust sides of the first-stage rotor pair 1 and the second-stage rotor pair 2 are also opposite to those of the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22.

[0046] In the above example, because the second-stage first rotor pair 11 and the second-stage second rotor pair 12 are symmetrically arranged, the axial gas force on the second-stage first rotor pair 11 is equal in magnitude and opposite in direction to the axial gas force on the second-stage second rotor pair 12, thus canceling each other out and achieving balance. Similarly, the first-stage first rotor pair 1 and the second-stage second rotor pair 2 are symmetrically arranged, so that the axial gas force on the first-stage first rotor pair 1 is equal in magnitude and opposite in direction to the axial gas force on the second-stage second rotor pair 2, thus canceling each other out and achieving balance. Likewise, the second-stage third rotor pair 21 and the second-stage fourth rotor pair 22 are symmetrically arranged, so that the axial gas force on the second-stage third rotor pair 21 is equal in magnitude and opposite in direction to the axial gas force on the second-stage fourth rotor pair 22, thus canceling each other out and achieving balance. Since the axial gas forces on each rotor pair are canceled out and balanced, the axial gas force balance of the rotor of the screw compressor of this utility model can be guaranteed.

[0047] Furthermore, since the intake sides of the first-stage rotor pair 1 and the second-stage rotor pair 2 are opposite to the intake sides of the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22, and the exhaust sides of the first-stage rotor pair 1 and the second-stage rotor pair 2 are also opposite to the exhaust sides of the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22, the radial gas force on the first-stage rotor pair 1 and the second-stage rotor pair 2 is opposite in direction to the radial gas force on the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22. This allows the radial gas force on the first-stage rotor pair 1 and the second-stage rotor pair 2 to at least partially or completely cancel out the radial gas force on the second-stage rotor pair 11, the second-stage rotor pair 12, the third-stage rotor pair 21, and the fourth-stage rotor pair 22, achieving a balance of radial gas force. This, in turn, improves the balance of the rotor radial gas force of the screw compressor of this invention.

[0048] In some embodiments, the resultant radial force on both the first stage rotor pair 1 and the second stage rotor pair 2 is F. 合1 The resultant radial force on the first rotor pair 11, the second rotor pair 12, the third rotor pair 21, and the fourth rotor pair 22 of the second stage is F. 合2 Among them, F 合1 With F 合2Since the two are equal in size and opposite in direction, they can completely offset all the radial gas forces that the screw compressor of this invention experiences during operation, thus achieving complete balance of the radial gas forces on the rotor.

[0049] In this design, the axial gas forces on each rotor pair are offset and balanced, thus the above-mentioned technical solution can completely offset all axial and radial forces experienced by the rotor during operation. The bearing load remains stable under all operating conditions, allowing for the use of a single small bearing for the final margin load support, resulting in more efficient and reliable rotor operation. Furthermore, because all axial and radial gas forces are balanced, the theoretical net gas force of the entire screw compressor is zero, achieving near-zero bearing load (only bearing the weight of parts, transportation and operational impacts, and mechanical positioning), significantly extending bearing life. Additionally, due to the substantial load balancing, the mechanical vibration of the screw compressor is also significantly reduced, decreasing noise caused by compressor mechanical and airflow pulsations.

[0050] In order to make the aforementioned F 合1 With F 合2 The two are equal in size and opposite in direction. In some embodiments, the aforementioned second-stage first rotor pair 11 and second-stage fourth rotor pair 22 are symmetrically arranged, so that the second-stage first rotor pair 11 and second-stage third rotor pair 21 have the same structure, and the second-stage second rotor pair 12 and second-stage fourth rotor pair 22 also have the same structure.

[0051] Among them, such as Figure 3-5 As shown, the radial resultant force on the male rotor of the first stage 1 relative to rotor 1 is F1, the radial resultant force on the female rotor of the first stage 1 relative to rotor 1 is F2, the radial resultant force on the male rotor of the second stage 1 relative to rotor 11 is F4, and the radial resultant force on the female rotor of the second stage 1 relative to rotor 11 is F3. Wherein, F1 and F3 are in opposite directions, and F1 = 2 * F3; F2 and F4 are in opposite directions, and F2 = 2 * F4.

[0052] In the above example, since the second-stage first rotor pair 11 and the second-stage second rotor pair 12 are symmetrically arranged, the radial resultant force on the male rotor of the second-stage second rotor pair 12 is F4, and the radial resultant force on the female rotor of the second-stage second rotor pair 12 is F3. Since the first-stage first rotor pair 1 and the second-stage second rotor pair 2 are symmetrically arranged, the radial resultant force on the male rotor of the second-stage second rotor pair 2 is F1, and the radial resultant force on the female rotor of the second-stage second rotor pair 2 is F2. Since the second-stage first rotor pair 11 and the second-stage fourth rotor pair 22 are symmetrically arranged, and the second-stage third rotor pair 21 is also symmetrically arranged with the second-stage fourth rotor pair 22, the radial resultant force on the male rotors of both the second-stage third rotor pair 21 and the second-stage fourth rotor pair 22 is F4, and the radial resultant force on the female rotors of both the second-stage third rotor pair 21 and the second-stage fourth rotor pair 22 is F3. With this arrangement, F1 and F3 are in opposite directions, and F1 = 2 * F3; F2 and F4 are in opposite directions, and F2 = 2 * F4, which can make F... 合1 With F 合2 The two are equal in size and opposite in direction.

[0053] In a specific application example, F1=F2 and F3=F4. In this example, both the male and female rotors of each rotor pair can be designed symmetrically, which facilitates F1=F2 and F3=F4. The symmetrical design of both the male and female rotors in each rotor pair offers advantages in terms of ease of design and manufacturing.

[0054] In some embodiments, the end face profiles of each rotor in both the first-stage first rotor pair 1 and the first-stage second rotor pair 2 are identical, and all are first end face profiles. The end face profiles of each rotor in the fourth-stage first rotor pair 11, the second-stage second rotor pair 12, the third-stage second rotor pair 21, and the fourth-stage second rotor pair 22 are identical, and all are second end face profiles. The first and second end face profiles are scaled proportionally.

[0055] In the example above, the first end face profile is used for the end face profiles of the male and female rotors within both the first-stage first rotor pair 1 and the first-stage second rotor pair 2, while the second end face profile is used for the end face profiles of the male and female rotors within the four second-stage first rotor pair 11, second-stage second rotor pair 12, third-stage second rotor pair 21, and fourth-stage second rotor pair 22. By making the first and second end face profiles scaled proportionally, the design, calculation, and manufacturing processes can be simplified.

[0056] The first end face profile and the second end face profile preferably have the same tooth curve type, and are scaled up proportionally to form a "similar end face profile" that resembles a "similar triangle".

[0057] In some implementations, such as Figure 2 As shown, the intake sides of the aforementioned first rotor pair 11, second rotor pair 12, third rotor pair 21, and fourth rotor pair 22 are all used to draw air from the exhaust sides of the first rotor pair 1 and the second rotor pair 2, thus enabling the screw compressor of this invention to achieve two-stage compression.

[0058] In some implementations, such as Figure 2 As shown, the aforementioned second-stage first rotor pair 11, second-stage second rotor pair 12, first-stage first rotor pair 1, first-stage second rotor pair 2, second-stage third rotor pair 21, and second-stage fourth rotor pair 22 are arranged sequentially along the first direction. The first direction is the axial direction of the shaft where the male rotor of each rotor pair is located.

[0059] In the example above, setting the primary rotor pair between the two sets of secondary rotor pairs is beneficial for the force balance of the rotor structure.

[0060] To achieve the function that the intake sides of the aforementioned four secondary rotor pairs 11, 12, 21, and 22 are all used to draw air from the exhaust sides of both the primary rotor pairs 1 and 2, in some embodiments, such as... Figure 2 As shown, the aforementioned screw compressor also includes a housing 4, which has a first compression chamber 41, a second compression chamber 42, and a third compression chamber 43 separated from each other. The aforementioned second-stage first rotor pair 11 and second-stage second rotor pair 12 are both located within the first compression chamber 41. The aforementioned first-stage first rotor pair 1 and second-stage second rotor pair 2 are both located within the second compression chamber 42. The aforementioned second-stage third rotor pair 21 and fourth-stage fourth rotor pair 22 are both located within the third compression chamber 43. The housing 4 has a first flow channel 3, which has a first air outlet 31, a second air outlet 32, a third air outlet 33, a fourth air outlet 34, and a fifth air outlet 35. Both the first air outlet 31 and the second air outlet 32 ​​are connected to the first compression chamber 41, and the intake side of the second-stage first rotor pair 11 draws air through the first air outlet 31, while the intake side of the second-stage second rotor pair 12 draws air through the second air outlet 32. Both the third air outlet 33 and the fourth air outlet 34 are connected to the third compression chamber 43. The intake side of the second-stage third rotor pair 21 draws air through the third air outlet 33, and the intake side of the second-stage fourth rotor pair 22 draws air through the fourth air outlet 34. The fifth air outlet 35 is connected to the second compression chamber 42, and the exhaust side of both the first-stage first rotor pair 1 and the second-stage second rotor pair 2 exhausts air through the fifth air outlet 35.

[0061] In the above example, the exhaust from both the first stage first rotor pair 1 and the first stage second rotor pair 2 flows into the first flow channel 3 through the fifth air outlet 35, and then splits into four streams. One stream flows into the intake side of the second stage first rotor pair 11 through the first air outlet 31, one stream flows into the intake side of the second stage second rotor pair 12 through the second air outlet 32, one stream flows into the intake side of the second stage third rotor pair 21 through the third air outlet 33, and one stream flows into the intake side of the second stage fourth rotor pair 22 through the fourth air outlet 34. This achieves the function that the intake sides of the two stages first rotor pair 11, second stage second rotor pair 12, second stage third rotor pair 21, and second stage fourth rotor pair 22 are all used to draw air from the exhaust side of both the first stage first rotor pair 1 and the first stage second rotor pair 2.

[0062] In some implementations, such as Figure 2 As shown, the aforementioned first flow channel 3 is symmetrically arranged about the midpoint a of the first stage first rotor pair 1 and the second stage second rotor pair 2.

[0063] In the above example, the shape of the first flow channel 3 affects the pressure loss of the airflow, and the pressure value will differ after the airflow passes through different flow channels. The mirror symmetry design of the first flow channel 3 of this utility model is to eliminate the situation where the force balance is incomplete and the force is not completely canceled due to pressure loss. In fact, slight differences are unavoidable, but the corresponding force difference will also be negligible and will not affect the operation of the shaft system. However, the design must ensure that the dimensions are consistent and completely mirrored, so that the error only occurs in application and production.

[0064] In some implementations, such as Figure 2 As shown, when the screw compressor includes a body 4, and the body 4 has a separated first compression chamber 41, second compression chamber 42, and third compression chamber 43; the second-stage first rotor pair 11 and the second-stage second rotor pair 12 are both located in the first compression chamber 41, the first-stage first rotor pair 1 and the first-stage second rotor pair 2 are both located in the second compression chamber 42, and the second-stage third rotor pair 21 and the second-stage fourth rotor pair 22 are both located in the third compression chamber 43, the aforementioned first compression chamber 41 has a first exhaust port 401, and the exhaust sides of both the second-stage first rotor pair 11 and the second-stage second rotor pair 12 exhaust through the first exhaust port 401. The third compression chamber 43 has a second exhaust port 403, and the exhaust sides of both the second-stage third rotor pair 21 and the second-stage fourth rotor pair 22 exhaust through the second exhaust port 403. The first exhaust port 401 and the second exhaust port 403 are symmetrically arranged about the midpoint a of the first-stage first rotor pair 1 and the first-stage second rotor pair 2 to further eliminate the situation where the force balance caused by pressure loss is incomplete or the force is not completely offset, thereby improving the balance of forces on the rotors.

[0065] In some implementations, such as Figure 2As shown, the aforementioned body 4 has a second flow channel 5, which has a second A air outlet 501, a second B air outlet 502, and a second C air outlet 503. Both the second B air outlet 502 and the second C air outlet 503 are connected to the second compression chamber 42. The intake side of the first stage first rotor pair 1 draws air through the second B air outlet 502, and the intake side of the first stage second rotor pair 2 draws air through the second C air outlet 503. The second A air outlet 501 penetrates the outer wall of the body 4. The second flow channel 5 is symmetrically arranged about the midpoint a of the first stage first rotor pair 1 and the first stage second rotor pair 2 to further eliminate the situation where the force balance caused by pressure loss is incomplete or the force is not completely offset, thereby improving the balance of forces on the rotors.

[0066] Regarding the design of the bearing placement, in the first example, as... Figure 6 As shown, a first bearing 6 is fitted onto the shaft segment between the male rotors of the aforementioned second-stage rotor pair 12 and the first-stage rotor pair 1, and a second bearing 7 is fitted onto the shaft segment between their female rotors. A third bearing 8 is fitted onto the shaft segment between the male rotors of the second-stage third rotor pair 21 and the first-stage second rotor pair 2, and a fourth bearing 9 is fitted onto the shaft segment between their female rotors. In the second example, as... Figure 7 As shown, each rotor pair has a fifth bearing 10a at both ends of the shaft where the male rotor is located, and a sixth bearing 10b at both ends of the shaft where the female rotor is located. In the third example, for cases with slightly weaker rigidity or considering excessive rotor length, bearings can be installed on all the aforementioned shaft sections to ensure stable mechanical operation. Specifically, a first bearing 6 is fitted on the shaft section between the male rotors of the second secondary rotor pair 12 and the first primary rotor pair 1, and a second bearing 7 is fitted on the shaft section between their female rotors. A third bearing 8 is fitted on the shaft section between the male rotors of the third secondary rotor pair 21 and the second primary rotor pair 2, and a fourth bearing 9 is fitted on the shaft section between their female rotors. Furthermore, each rotor pair has a fifth bearing 10a at both ends of the shaft where the male rotor is located, and a sixth bearing 10b at both ends of the shaft where the female rotor is located. In this third example, the increased number of bearings is solely for stabilizing the shaft system's rigidity. Compared to the case where a single rotor pair requires approximately 10 bearings, the number of bearings in this third example is significantly reduced.

[0067] It should be noted here that, in order to make the directions of F1 and F3 opposite, and F1 = 2 * F3; and the directions of F2 and F4 opposite, and F2 = 2 * F4, in order to counteract all the radial gas forces on the rotor, a specific design method is given below:

[0068] 1. Determine two sets of male and female rotor end face profiles, namely the aforementioned first end face profile and second end face profile. The first end face profile is used for the first rotor pair 1 and the second rotor pair 2 of the first stage, and the second end face profile is used for the aforementioned first rotor pair 11, second rotor pair 12, third rotor pair 21, and fourth rotor pair 22 of the second stage. To simplify the design, calculation, and production, the first and second end face profiles are preferably of the same component tooth curve type, and are only scaled proportionally to form "similar end face profiles" similar to "similar triangles".

[0069] 2. Determine the working section length and exhaust port shape and size for both the first stage rotor pair 1 and the second stage rotor pair 2. The exhaust port here is the aforementioned fifth air outlet 35. Simulation calculations are used to obtain the force results for both the first stage rotor pair 1 and the second stage rotor pair 2, including the magnitude and direction of the forces. Since the first stage rotor pair 1 and the second stage rotor pair 2 are completely mirror images of each other, the axial gas forces on them will inevitably cancel each other out. The radial gas forces are two sets of forces with the same direction and equal magnitude, namely F1 and F2, with force directions at angles α and β respectively (e.g., ...). Figure 3 (As shown).

[0070] 3. Based on the forces F1 and F2, determine the lengths of the four pairs of rotors: the first rotor pair 11, the second rotor pair 12, the third rotor pair 21, and the fourth rotor pair 22. Through the process of "determining the length - calculating the force value - correcting the length", four sets of forces are finally obtained, all of which are F3 and F4, and 2 × F3 = F1, 2 × F4 = F2 (e.g., ...). Figure 4 (As shown). Note that due to the use of a "similar end-face profile" design, when the lengths of the four secondary rotor pairs (11, 12, 21, 22, and 22) ensure 2×F3=F1, 2×F4=F2 is also inevitable. However, if the primary and secondary rotor pairs use different types of dissimilar end-face profiles, ensuring 2×F3=F1 makes it difficult to ensure 2×F4=F2. In this case, profile modification is necessary to meet the requirements. Theoretically, it is possible to eventually modify the profiles to achieve 2×F3=F1 and 2×F4=F2, but this is very complicated.

[0071] 4. Similarly, the force directions of the four secondary rotor pairs 11, 12, 21, and 22 are determined based on the shape and size of the exhaust port. Because of the use of "similar end face profiles," "similar exhaust ports" are directly used here. That is, the shape and size of the aforementioned first exhaust port 401 and second exhaust port 403 are proportionally scaled to the shape and size of the aforementioned fifth air outlet 35. The "similar exhaust ports" are placed in opposite orientations (as shown in the attached diagram). Figure 2As shown, the intake of both the first rotor pair 1 and the second rotor pair 2 is at the top, and the exhaust is at the bottom; the second rotor pairs are completely opposite (the intake of the first rotor pair 11, the second rotor pair 12, the third rotor pair 21, and the fourth rotor pair 22 is at the bottom, and the exhaust is at the top). In this way, the force direction of the four second rotor pairs 11, 12, 21, and 22 is completely consistent and completely opposite to that of the first rotor pair 1 and the second rotor pair 2.

[0072] This utility model also provides an air conditioner that may include any of the screw compressors described above. Because the air conditioner uses the screw compressor, it can improve the balance of radial gas forces on the rotor while ensuring the axial gas force balance of the rotor.

[0073] For ease of understanding, the overall structure of this utility model will be described below, and its working principle will be explained.

[0074] The screw compressor of this utility model is a multi-rotor two-stage compressor structure. It achieves complete cancellation of gas forces by using two types of rotor pairs (i.e., primary rotor pairs and secondary rotor pairs), three sets of rotor pairs (the first set consists of the first set of the secondary first rotor pair 11 and the second set of the secondary second rotor pair 12, the second set consists of the first set of the primary first rotor pair 1 and the second set of the primary second rotor pair 2, and the third set consists of the second set of the secondary third rotor pair 21 and the fourth set of the secondary fourth rotor pair 22), with four rotors symmetrically arranged in each set, for a total of eight types and twelve rotors. This greatly reduces the load on the shaft system and the load variation under all operating conditions, simplifies the structure, reduces costs, improves bearing life and reliability, and can also reduce noise and vibration caused by compressor mechanical and airflow pulsation to a certain extent.

[0075] As attached Figure 1 As shown, the present invention comprises a total of 12 rotors: the second-stage first rotor pair 11, the second-stage second rotor pair 12, the first-stage first rotor pair 1, the first-stage second rotor pair 2, the second-stage third rotor pair 21, and the second-stage fourth rotor pair 22. Six rotors are connected in series on one shaft. The rotor pairs are divided into two diameters and two rotation directions.

[0076] The working process of this screw compressor is as follows: Gas enters the compressor through the second A outlet 501 and is divided into two paths, which are compressed by the first stage first rotor pair 1 and the first stage second rotor pair 2 respectively. The axial forces generated in this process are opposite and cancel each other out. After the two exhaust streams merge, they flow into the first flow channel 3 through the fifth outlet 35, and then are divided into four paths, which enter the first outlet 31, the second outlet 32, the third outlet 33 and the fourth outlet 34 respectively. They are compressed by the second stage first rotor pair 11, the second stage second rotor pair 12, the second stage third rotor pair 21 and the second stage fourth rotor pair 22 respectively, and then discharged through two exhaust ports, namely the first exhaust port 401 and the second exhaust port 403.

[0077] In this process, due to the completely mirrored rotor pairs, the first flow channel 3 and the second flow channel 5, the axial forces at both ends of the split surface a between the first stage first rotor pair 1 and the first stage second rotor pair 2 are canceled out by the same magnitude and opposite direction generated by several perfectly symmetrical rotor pairs, and the engineering deviations present are borne by a small number of bearings.

[0078] As attached Figure 3-5 As shown, the design of the exhaust port opening ensures that the angles of several rotors relative to the exhaust port are consistent, while those opposite to the exhaust direction are attached. Figure 3 and 4 The direction of the gas force shown can also be completely controlled, ensuring that the resultant radial gas forces of the first and second stages of compression are of the same magnitude and opposite in direction. If perfect gas force balance is desired, rotors and bore housing channels with different sizes but proportionally similar dimensions should be used to achieve identical force angles. Figure 3 and 4 The angles α and β shown ensure the direction, while the rotor length ensures the magnitude of the force. The magnitude and direction are determined to cancel each other out. In actual use, some compromises in balance can be made based on the user's needs to better suit the specific operating conditions. In this case, although some force may not be completely canceled out, it is very small and can be handled by a slightly larger bearing. Similarly, axial force can also be designed with a certain degree of imbalance to ensure the deviation is controllable, using a unidirectional bearing.

[0079] Here, α and β are angular dimensions used during the design process to conveniently determine the radial force direction of the primary and secondary rotor pairs. Each rotor pair consists of a male rotor and a female rotor. α and β correspond to the radial force calibration angles of the male and female rotors, respectively. During the design process, it is essential to ensure that the α and β angles of the primary and secondary rotor pairs are equivalent, thus guaranteeing that the rotor force directions are aligned. Refer to the appendix for further details. Figure 3The directions of F1 and F3, and F2 and F4 are shown in the diagram. In practice, under the same standard, the angle α corresponding to the force F1 on the first-stage rotor pair should be (180°+α) for the opposite F3 to be accurate. The same applies to F2 and F4.

[0080] When the rotor pair is working, the male and female rotors will bear certain forces under the corresponding intake and exhaust pressures. When the working pressures at each point are determined, the magnitude of the force on rotors of different sizes can be calculated precisely, and the degree of torsion of different rotors and the opening position of the intake / exhaust ports can be precisely controlled in terms of the direction of the force. Based on this, the aforementioned rotor pairs can be designed to ensure that under the target working conditions (i.e., under the target intake, exhaust and intermediate process pressures), the radial resultant force of the first-stage rotor pair and the radial resultant force of the second-stage rotor pair are equal in magnitude and opposite in direction.

[0081] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0082] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model. The above description is only a preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A screw compressor, characterized in that: It includes multiple rotor pairs, each rotor pair having a pair of meshing male rotor and female rotor, the male rotors of each rotor pair being coaxially arranged, and the female rotors of each rotor pair being coaxially arranged; The rotor pairs are respectively a second-stage first rotor pair (11), a second-stage second rotor pair (12), a first-stage first rotor pair (1), a second-stage second rotor pair (2), a second-stage third rotor pair (21), and a second-stage fourth rotor pair (22); the second-stage first rotor pair (11) and the second-stage second rotor pair (12) are symmetrically arranged, the first-stage first rotor pair (1) and the second-stage second rotor pair (2) are symmetrically arranged, and the second-stage third rotor pair (21) and the second-stage fourth rotor pair (22) are symmetrically arranged. Each of the rotor pairs draws air from one side of its respective meshing position and exhausts air from the other side of its respective meshing position; and the air intake sides of the first primary rotor pair (1) and the second primary rotor pair (2) are opposite to the air intake sides of the first secondary rotor pair (11), the second secondary rotor pair (12), the third secondary rotor pair (21), and the fourth secondary rotor pair (22).

2. The screw compressor according to claim 1, characterized in that: The resultant radial force on the first stage first rotor pair (1) and the second stage second rotor pair (2) is F. 合1 The radial resultant force on the four secondary rotor pairs (11), (12), (21), and (22) is F. 合2 ; Among them, F 合1 With F 合2 The two are equal in size and opposite in direction.

3. The screw compressor according to claim 2, characterized in that: The second-stage first rotor pair (11) and the second-stage fourth rotor pair (22) are symmetrically arranged; and the radial resultant force on the male rotor of the first-stage first rotor pair (1) is F1, the radial resultant force on the female rotor of the first-stage first rotor pair (1) is F2, the radial resultant force on the male rotor of the second-stage first rotor pair (11) is F4, and the radial resultant force on the female rotor of the second-stage first rotor pair (11) is F3. Among them, F1 and F3 are in opposite directions, and F1 = 2 * F3; F2 and F4 are in opposite directions, and F2 = 2 * F4.

4. The screw compressor according to any one of claims 1-3, characterized in that: The end face profiles of each rotor in the first-stage first rotor pair (1) and the first-stage second rotor pair (2) are consistent and are all first end face profiles; the end face profiles of each rotor in the second-stage first rotor pair (11), the second-stage second rotor pair (12), the third-stage second rotor pair (21), and the fourth-stage second rotor pair (22) are consistent and are all second end face profiles; The first end face profile and the second end face profile are scaled proportionally.

5. The screw compressor according to any one of claims 1-3, characterized in that: The intake sides of the four secondary rotor pairs (11), (12), (21), and (22) are all used to draw air from the exhaust sides of the primary rotor pairs (1) and (2).

6. The screw compressor according to claim 5, characterized in that: The second-stage first rotor pair (11), the second-stage second rotor pair (12), the first-stage first rotor pair (1), the first-stage second rotor pair (2), the second-stage third rotor pair (21), and the second-stage fourth rotor pair (22) are arranged sequentially along a first direction, which is the axial direction of the shaft where the male rotor of each rotor pair is located.

7. The screw compressor according to claim 6, characterized in that: It also includes a body (4), which has a first compression chamber (41), a second compression chamber (42) and a third compression chamber (43) separated from each other; the second-stage first rotor pair (11) and the second-stage second rotor pair (12) are both disposed in the first compression chamber (41), the first-stage first rotor pair (1) and the second-stage second rotor pair (2) are both disposed in the second compression chamber (42), and the second-stage third rotor pair (21) and the second-stage fourth rotor pair (22) are both disposed in the third compression chamber (43); The machine body (4) has a first flow channel (3) inside, which has a first air outlet (31), a second air outlet (32), a third air outlet (33), a fourth air outlet (34), and a fifth air outlet (35). The first air outlet (31) and the second air outlet (32) are both connected to the first compression chamber (41), and the intake side of the second-stage first rotor pair (11) draws air through the first air outlet (31), while the intake side of the second-stage second rotor pair (12) draws air through the second air outlet (32). The third air outlet (33) and the fourth air outlet (34) are both connected to the third compression chamber (43), and the air intake side of the second-stage third rotor pair (21) draws air through the third air outlet (33), and the air intake side of the second-stage fourth rotor pair (22) draws air through the fourth air outlet (34); the fifth air outlet (35) is connected to the second compression chamber (42), and the exhaust side of both the first-stage first rotor pair (1) and the first-stage second rotor pair (2) exhausts air through the fifth air outlet (35).

8. The screw compressor according to claim 7, characterized in that: The first flow channel (3) is symmetrically arranged about the midpoint (a) of the first stage first rotor pair (1) and the first stage second rotor pair (2).

9. The screw compressor according to any one of claims 1-3 and 6-8, characterized in that: When the screw compressor includes a body (4), and the body (4) has a separated first compression chamber (41), a second compression chamber (42), and a third compression chamber (43); the second-stage first rotor pair (11) and the second-stage second rotor pair (12) are both disposed in the first compression chamber (41), the first-stage first rotor pair (1) and the second-stage second rotor pair (2) are both disposed in the second compression chamber (42), and the second-stage third rotor pair (21) and the second-stage fourth rotor pair (22) are both disposed in the third compression chamber (43), wherein, The first compression chamber (41) has a first exhaust port (401), and the exhaust sides of both the second-stage first rotor pair (11) and the second-stage second rotor pair (12) are exhausted through the first exhaust port (401). The third compression chamber (43) has a second exhaust port (403), and the exhaust sides of both the second-stage third rotor pair (21) and the second-stage fourth rotor pair (22) are exhausted through the second exhaust port (403). The first exhaust port (401) and the second exhaust port (403) are symmetrically arranged about the midpoint (a) of the first-stage first rotor pair (1) and the second-stage second rotor pair (2). And / or, the body (4) has a second flow channel (5), the second flow channel (5) has a second A air outlet (501), a second B air outlet (502) and a second C air outlet (503), the second B air outlet (502) and the second C air outlet (503) are both connected to the second compression chamber (42), and the intake side of the first stage first rotor pair (1) draws air through the second B air outlet (502), the intake side of the first stage second rotor pair (2) draws air through the second C air outlet (503), and the second A air outlet (501) penetrates the outer wall of the body (4); the second flow channel (5) is symmetrically arranged about the midpoint (a) of the first stage first rotor pair (1) and the first stage second rotor pair (2).

10. The screw compressor according to any one of claims 1-3 and 6-8, characterized in that: A first bearing (6) is fitted on the shaft segment between the male rotors of the second secondary rotor pair (12) and the first primary rotor pair (1), and a second bearing (7) is fitted on the shaft segment between the female rotors of the two pairs; a third bearing (8) is fitted on the shaft segment between the male rotors of the third secondary rotor pair (21) and the first primary rotor pair (2), and a fourth bearing (9) is fitted on the shaft segment between the female rotors of the two pairs; And / or, each of the male rotor shafts of each rotor pair is provided with a fifth bearing (10a) at both ends, and each of the female rotor shafts of each rotor pair is provided with a sixth bearing (10b) at both ends.

11. An air conditioner, characterized in that: The screw compressor includes any one of claims 1-10.

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