Screw compressor

Abstract

A screw compressor comprises a shell, a male rotor and a female rotor, the male rotor and the female rotor are mounted in the shell, an air inlet seat is arranged on one side of the shell, an air outlet seat is arranged on the other side of the shell, the male rotor is mounted on the air inlet seat through a first inlet end bearing and mounted on the air outlet seat through a first outlet end bearing, and the female rotor is mounted on the air outlet seat through a second outlet end bearing. The compressor is characterized in that the female rotor is installed on the air inlet seat through a second inlet end bearing and installed on the air outlet seat through a second row end bearing and a third row end bearing, and the second row end bearing and the third row end bearing can bear axial force and radial force. Main machine vibration and rotor deviation of the screw compressor are reduced, the stability and efficiency of machine operation are improved, and the service life of the machine operation is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of compressors, in particular to a screw compressor. Background Art

[0002] The Chinese invention patent application with application publication number CN113803252 A discloses a screw compressor, the structure of which is as follows: Figure 1 As shown, it includes a shell 1a, and a male rotor 2a and a female rotor 3a installed in the shell 1a, an intake seat 4a is arranged on one side of the shell 1a and an exhaust seat 5a is arranged on the other side, the male rotor 2a is installed on the intake seat 4a through a first intake-end bearing 6a, and is installed on the exhaust seat 5a through a first row-end bearing 7a, and the female rotor 3a is installed on the intake seat 4a through a second intake-end bearing 8a, and is installed on the exhaust seat 5a through a second row-end bearing 9a.

[0003] However, the existing screw compressors have the following technical problems: low-pressure gas is compressed by the rotor and high-pressure gas is discharged from the exhaust seat 5a. Due to the large airflow impact and pressure change of the high-pressure gas, the vibration of the main engine and the displacement of the rotor are large during the compression process, resulting in additional power consumption and large wear, affecting the stability, efficiency and service life of the machine. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a screw compressor which reduces the vibration of the main engine and the deviation of the rotor and improves the stability, efficiency and service life of the machine operation.

[0005] The technical solution of the utility model is: a screw compressor, including a shell, and a male rotor and a female rotor installed in the shell, an intake seat is arranged on one side of the shell and an exhaust seat is arranged on the other side, the male rotor is installed on the intake seat through a first intake end bearing, and is installed on the exhaust seat through a first row end bearing, the female rotor is installed on the intake seat through a second intake end bearing, and is installed on the exhaust seat through a second row end bearing and a third row end bearing, and the second row end bearing and the third row end bearing can both withstand axial force and radial force.

[0006] After adopting the above structure, the utility model has the following advantages:

[0007] The utility model provides a double-bearing structure on the exhaust end of the female rotor of the screw compressor, and both bearings can withstand axial force and radial force, and can overcome the strong airflow impact and pressure change of the high-pressure gas on the exhaust end from both axial and radial directions, reduce the vibration of the main engine and the deviation of the rotor, so that the system operation is more stable, more efficient, and less worn, while reducing the additional power consumption caused by the deviation of the rotor; secondly, the double-bearing structure can better disperse and withstand the force generated when the rotor is working, avoid a single bearing from being subjected to excessive pressure and causing wear or damage, and improve the service life of the machine; thirdly, after adopting the double-bearing structure, the oil pressure on the rotor is smaller during low-frequency operation, and the specific power is more stable during full-frequency operation; all of the above improve the stability, efficiency and service life of the machine operation.

[0008] Preferably, the second row end bearings and the third row end bearings are tapered roller bearings. Tapered roller bearings have strong load-bearing capacity and high rigidity. They are arranged at the exhaust end of the female rotor and can better withstand large axial and radial forces to overcome the strong airflow impact and pressure changes of high-pressure gas, reduce host vibration and rotor deviation; in addition, tapered roller bearings rotate stably and with high precision, which can further improve the stability and transmission efficiency of machine operation and reduce energy loss.

[0009] Preferably, the first row end bearing is a tapered roller bearing. The tapered roller bearing has a strong load-bearing capacity and high rigidity. It is set at the exhaust end of the male rotor and can better withstand large axial and radial forces to overcome the strong airflow impact and pressure changes of high-pressure gas, reduce the vibration of the main engine and the rotor deviation; in addition, the tapered roller bearing has stable rotation and high precision, which can further improve the stability of the machine operation and transmission efficiency and reduce energy loss.

[0010] Preferably, the first inlet bearing is a ball bearing or a cylindrical roller bearing. Since the inlet end of the male rotor is mainly subjected to radial force, and ball bearings and cylindrical roller bearings have excellent radial load characteristics, it is more appropriate to select a ball bearing or a cylindrical roller bearing according to the force characteristics of this position, which can not only better withstand radial force, but also reasonably combine with bearings at other positions to improve the stability and operation efficiency of the overall structure.

[0011] Preferably, the second inlet bearing is a ball bearing or a cylindrical roller bearing. Since the inlet end of the female rotor is mainly subjected to radial force, and ball bearings and cylindrical roller bearings have excellent radial load characteristics, it is more appropriate to select ball bearings or cylindrical roller bearings according to the force characteristics of this position, which can not only better withstand radial force, but also reasonably combine with bearings at other positions to improve the stability and operation efficiency of the overall structure.

[0012] Preferably, the third row end bearing is arranged on the side of the second row end bearing away from the air inlet seat, a limiting step is arranged on the exhaust seat and located on the side of the second row end bearing close to the air inlet seat, and a locking nut is arranged on the side of the third row end bearing away from the air inlet seat on the female rotor. When the locking nut is tightened, the third row end bearing is pressed together with the second row end bearing, and the outer ring of the second row end bearing abuts against the limiting step and the inner ring of the third row end bearing abuts against the locking nut. This setting uses the limiting step and the locking nut to limit the two sides of the double bearings, so that the third row end bearing is installed on the exhaust seat of the female rotor together with the second row end bearing, and the installation structure is simple and the limiting is reliable.

[0013] Preferably, a bearing pressure ring is provided on the exhaust seat and on the side of the third row end bearing away from the air inlet seat. The bearing pressure ring is sleeved outside the locking nut, and one side of the bearing pressure ring abuts against the outer ring of the third row end bearing, and the other side abuts against the exhaust seat through an elastic member. This setting can limit the outer ring of the third row end bearing, making the rotor run more stable and reliable; in addition, since the machine will undergo thermal expansion and cold contraction due to temperature changes during operation, the elastic member provided on one side of the bearing pressure ring can well compensate for these changes, avoid loosening or overtightening caused by thermal expansion and cold contraction, thereby maintaining a constant preload force of the bearing structure; in addition, the elastic member also has good shock absorption and damping characteristics, can absorb vibration and impact during equipment operation, protect bearings and related components, and reduce wear and damage.

[0014] Preferably, a plurality of protrusions for abutting against the outer ring of the third row end bearing are evenly arranged on the side of the bearing pressure ring close to the third row end bearing. The plurality of protrusions are arranged on the bearing pressure ring so that it can reliably abut against the third row end bearing at all positions, and this point-to-surface abutment method is more lightweight and has lower requirements on assembly accuracy than the surface-to-surface abutment method.

[0015] Preferably, the elastic member is a wave spring, one side of which abuts against the bearing pressure ring, and the other side abuts against the exhaust seat. Compared with ordinary springs, wave springs can provide greater preload or load in a smaller axial space, and are very suitable for occasions with limited space, making the overall structure more compact.

[0016] Preferably, the thickness of the locking nut is reduced on one side away from the third row end bearing to form a knocking edge, and a positioning groove is provided on the female rotor at a position corresponding to the knocking edge, for knocking the knocking edge portion into the positioning groove. This arrangement can knock the knocking edge portion of the locking nut into the positioning groove of the female rotor, so that the locking nut will not loosen when rotating. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional view of an existing screw compressor;

[0018] Figure 2 It is a cross-sectional view of the screw compressor of the utility model;

[0019] Figure 3 for Figure 2 A local enlarged schematic diagram of the middle A;

[0020] Figure 4 This is a schematic diagram of the structure of the screw compressor of the utility model after the exhaust seat and the end cover plate are hidden;

[0021] In the prior art figure: 1a-housing, 2a-male rotor, 3a-female rotor, 4a-inlet seat, 5a-exhaust seat, 6a-first inlet end bearing, 7a-first row end bearing, 8a-second inlet end bearing, 9a-second row end bearing;

[0022] In the utility model: 1-housing, 2-male rotor, 3-female rotor, 4-inlet seat, 5-exhaust seat, 6-first inlet end bearing, 7-first row end bearing, 8-second inlet end bearing, 9-second row end bearing, 10-third row end bearing, 11-compression chamber, 12-end cover plate, 13-limiting step, 14-locking nut, 15-outer ring of second row end bearing, 16-inner ring of third row end bearing, 17-bearing pressure ring, 18-elastic member, 19-bump, 20-knocking edge, 21-positioning groove, 22-outer ring of third row end bearing. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Example:

[0025] like Figure 2-4 As shown, a screw compressor comprises a shell 1, and a male rotor 2 and a female rotor 3 installed in the shell 1, an intake seat 4 is arranged on one side of the shell 1 and an exhaust seat 5 is arranged on the other side, the male rotor 2 is installed on the intake seat 4 through a first intake end bearing 6, and is installed on the exhaust seat 5 through a first row end bearing 7, the female rotor 3 is installed on the intake seat 4 through a second intake end bearing 8, and is installed on the exhaust seat 5 through a second row end bearing 9 and a third row end bearing 10, the second row end bearing 9 and the third row end bearing 10 can both withstand axial force and radial force; a compression chamber 11 is located inside the shell 1 and between the intake seat 4 and the exhaust seat 5; in this embodiment, the intake seat 4 is integrally formed in the shell 1, the exhaust seat 5 is detachably connected to the shell 1, one side of the exhaust seat 5 is connected to the compression chamber 11, and an end cover plate 12 for closing the exhaust seat 5 is arranged on the other side, and the end cover plate 12 is also detachably connected to the exhaust seat 5, so as to facilitate the installation of internal components.

[0026] The screw compressor of the utility model is provided with a double-bearing structure on the exhaust end of the female rotor 3, and the two bearings can withstand axial force and radial force, and can overcome the strong airflow impact and pressure change of the high-pressure gas on the exhaust end from the axial and radial directions at the same time, reduce the vibration of the main engine and the rotor deviation, so that the system operation is more stable, more efficient, and less worn, while reducing the additional power consumption caused by the rotor deviation; secondly, the double-bearing structure can better disperse and withstand the force generated when the rotor is working, avoid a single bearing from being subjected to excessive pressure and causing wear or damage, and improve the service life of the machine; thirdly, after adopting the double-bearing structure, the oil pressure applied to the rotor is smaller during low-frequency operation, and the specific power is more stable during full-frequency operation; all of the above improve the stability, efficiency and service life of the machine operation.

[0027] The second row end bearing 9 and the third row end bearing 10 are both tapered roller bearings. The tapered roller bearing has strong load-bearing capacity and high rigidity. It is set at the exhaust end of the female rotor 3, which can better withstand large axial and radial forces to overcome the strong airflow impact and pressure changes of high-pressure gas, reduce the vibration of the main engine and the displacement of the rotor; in addition, the tapered roller bearing has stable rotation and high precision, which can further improve the stability and transmission efficiency of the machine operation and reduce energy loss.

[0028] The first row end bearing 7 is a tapered roller bearing. The tapered roller bearing has strong load-bearing capacity and high rigidity. It is set at the exhaust end of the male rotor 2, which can better withstand large axial and radial forces to overcome the strong airflow impact and pressure changes of high-pressure gas, reduce the vibration of the main engine and the deviation of the rotor; in addition, the tapered roller bearing has stable rotation and high precision, which can further improve the stability and transmission efficiency of the machine operation and reduce energy loss.

[0029] The first inlet bearing 6 is a ball bearing or a cylindrical roller bearing. Since the inlet end of the male rotor 2 is mainly subjected to radial force, and ball bearings and cylindrical roller bearings have excellent radial load characteristics, it is more appropriate to select a ball bearing or a cylindrical roller bearing according to the force characteristics of this position, which can not only better withstand radial force, but also reasonably combine with bearings at other positions to improve the stability and operation efficiency of the overall structure.

[0030] The second inlet bearing 8 is a ball bearing or a cylindrical roller bearing. Since the inlet end of the female rotor 3 is mainly subjected to radial force, and ball bearings and cylindrical roller bearings have excellent radial load characteristics, it is more appropriate to select ball bearings or cylindrical roller bearings according to the force characteristics of this position, which can not only better withstand radial force, but also reasonably combine with bearings at other positions to improve the stability and operation efficiency of the overall structure.

[0031] The third row end bearing 10 is arranged on the side of the second row end bearing 9 away from the air inlet seat 4, a limiting step 13 is arranged on the exhaust seat 5 and on the side of the second row end bearing 9 close to the air inlet seat 4, and a locking nut 14 is arranged on the female rotor 3 and on the side of the third row end bearing 10 away from the air inlet seat 4. When the locking nut 14 is tightened, the third row end bearing 10 is pressed together with the second row end bearing 9, and the outer ring 15 of the second row end bearing 9 abuts against the limiting step 13 and the inner ring 16 of the third row end bearing 10 abuts against the locking nut 14. This setting uses the limiting step 13 and the locking nut 14 to limit the two sides of the double bearings, so that the third row end bearing 10 is installed on the exhaust seat 5 of the female rotor 3 together with the second row end bearing 9, and the installation structure is simple and the limiting is reliable.

[0032] A bearing pressing ring 17 is also provided on the exhaust seat 5 and located on the side of the third row end bearing 10 away from the intake seat 4. The bearing pressing ring 17 is sleeved outside the locking nut 14. One side of the bearing pressing ring 17 abuts against the outer ring 22 of the third row end bearing 10, and the other side abuts against the exhaust seat 5 through the elastic member 18. This setting can limit the outer ring 22 of the third row end bearing 10, making the rotor run more stable and reliable; in addition, since the machine will undergo thermal expansion and cold contraction due to temperature changes during operation, the elastic member 18 is provided on one side of the bearing pressing ring 17 to compensate for these changes well, avoiding looseness or overtightening caused by thermal expansion and cold contraction, thereby maintaining a constant preload force of the bearing structure; in addition, the elastic member 18 also has good shock absorption and shock reduction characteristics, which can absorb vibration and impact during equipment operation, protect bearings and related components, and reduce wear and damage.

[0033] A plurality of protrusions 19 are evenly arranged on one side of the bearing pressure ring 17 close to the third row end bearing 10 for abutting against the outer ring 22 of the third row end bearing 10. The plurality of protrusions 19 are arranged on the bearing pressure ring 17 so that it can reliably abut against the third row end bearing 10 at all positions, and this point-to-surface abutment method is more lightweight and has lower requirements on assembly accuracy than the surface-to-surface abutment method.

[0034] The elastic member 18 is a wave spring, one side of which abuts against the bearing pressure ring 17, and the other side abuts against the end cover plate 12 of the exhaust seat 5. Compared with ordinary springs, the wave spring can provide a greater preload or load in a smaller axial space. It is very suitable for occasions with limited space and can make the overall structure more compact.

[0035] The thickness of the locking nut 14 on the side away from the third row end bearing 10 is reduced to form a knocking edge 20, and a positioning groove 21 is provided on the female rotor 3 at a position corresponding to the knocking edge 20, for knocking the knocking edge 20 part into the positioning groove 21. This setting can knock the knocking edge 20 part of the locking nut 14 into the positioning groove 21 of the female rotor 3, so that the locking nut 14 will not loosen when rotating.

Claims

1. A screw compressor, comprising a housing (1), and a male rotor (2) and a female rotor (3) mounted in the housing (1), wherein an air inlet seat (4) is arranged on one side of the housing (1) and an air discharge seat (5) is arranged on the other side of the housing (1), wherein the male rotor (2) is mounted on the air inlet seat (4) via a first inlet end bearing (6) and is mounted on the air discharge seat (5) via a first row end bearing (7), characterized in that: The female rotor (3) is mounted on the intake seat (4) via a second intake end bearing (8), and is mounted on the exhaust seat (5) via a second row end bearing (9) and a third row end bearing (10), wherein the second row end bearing (9) and the third row end bearing (10) can both withstand axial force and radial force.

2. A screw compressor according to claim 1, characterized in that: The second row end bearings (9) and the third row end bearings (10) are both tapered roller bearings.

3. A screw compressor according to claim 1, characterized in that: The first row end bearings (7) are tapered roller bearings.

4. A screw compressor according to claim 1, characterized in that: The first inlet bearing (6) is a ball bearing or a cylindrical roller bearing.

5. A screw compressor according to claim 1, characterized in that: The second inlet bearing (8) is a ball bearing or a cylindrical roller bearing.

6. A screw compressor according to claim 1, characterized in that: The third row end bearing (10) is arranged on the side of the second row end bearing (9) away from the air inlet seat (4), a limiting step (13) is provided on the exhaust seat (5) and located on the side of the second row end bearing (9) close to the air inlet seat (4), and a locking nut (14) is provided on the female rotor (3) and located on the side of the third row end bearing (10) away from the air inlet seat (4). When the locking nut (14) is tightened, the third row end bearing (10) and the second row end bearing (9) are pressed together, and the outer ring (15) of the second row end bearing (9) abuts against the limiting step (13) and the inner ring (16) of the third row end bearing (10) abuts against the locking nut (14).

7. A screw compressor according to claim 6, characterized in that: A bearing pressure ring (17) is also provided on the exhaust seat (5) and located on the side of the third row end bearing (10) away from the intake seat (4). The bearing pressure ring (17) is sleeved outside the locking nut (14). One side of the bearing pressure ring (17) abuts against the outer ring (22) of the third row end bearing (10), and the other side abuts against the exhaust seat (5) through an elastic member (18).

8. A screw compressor according to claim 7, characterized in that: A plurality of protrusions (19) for abutting against the outer ring (22) of the third row end bearing (10) are evenly arranged on the side of the bearing pressure ring (17) close to the third row end bearing (10).

9. A screw compressor according to claim 7, characterized in that: The elastic member (18) is a wave spring, one side of which abuts against the bearing pressure ring (17), and the other side of which abuts against the exhaust seat (5).

10. A screw compressor according to claim 6, characterized in that: The thickness of the locking nut (14) on the side away from the third row end bearing (10) is reduced to form a knocking edge (20), and a positioning groove (21) is provided on the female rotor (3) at a position corresponding to the knocking edge (20) for knocking the knocking edge (20) partially into the positioning groove (21).

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