WO2023071453A1

WO2023071453A1 - Rotating shaft assembly and magnetic suspension compressor

Info

Publication number: WO2023071453A1
Application number: PCT/CN2022/113593
Authority: WO
Inventors: 胡余生; 郭伟林; 龚高; 张芳; 李欣
Original assignee: 珠海格力电器股份有限公司
Priority date: 2021-10-28
Filing date: 2022-08-19
Publication date: 2023-05-04
Also published as: CN113864339A

Abstract

The present disclosure provides a rotating shaft assembly and a magnetic suspension compressor. The rotating shaft assembly comprises a rotor assembly, a bearing, a protective ferrule, and an axial limiting assembly; the rotor assembly comprises a rotating shaft; the bearing comprises a first through hole that penetrates through the bearing in an axial direction; the rotating shaft penetrates through the first through hole; the protective ferrule is clamped between the rotating shaft and the bearing; and the axial limiting assembly is configured to limit the axial position of the bearing relative to the rotating shaft. The rotating shaft assembly of the present disclosure effectively protects the bearing, so that the bearing is not prone to damage.

Description

Shaft assembly and magnetic levitation compressor

Cross References to Related Applications

This disclosure is based on the application with CN application number 202111263500.0 and the application date is October 28, 2021, and claims its priority. The disclosure content of this CN application is hereby incorporated into this disclosure as a whole.

technical field

The present disclosure relates to the technical field of compressors, in particular to a rotating shaft assembly and a magnetic levitation compressor.

Background technique

In order to achieve high-speed rotation of the shaft of the centrifugal compressor, a magnetic bearing is used in the related art to rotatably support the shaft of the centrifugal compressor. The magnetic bearing is used to support the shaft, and no frictional heat is generated between the shaft and the bearing. Therefore, it is possible to prevent the shaft from seizing to the bearing due to frictional heat, and to achieve high-speed rotation of the shaft.

However, since the magnetic bearing is not in direct contact with the shaft, the supporting strength of the magnetic bearing is low. Therefore, in the event of a power outage, an earthquake, etc., the shaft is displaced from the reference position and the shaft comes into contact with the magnetic bearing, which may damage the magnetic bearing.

Contents of the invention

An embodiment of the present invention provides a shaft assembly, including:

the rotor assembly, including the shaft;

The bearing includes a first through hole running through its axial direction; the rotating shaft passes through the first through hole;

a protective collar interposed between the rotating shaft and the inner wall of the first through hole; and

The axial limit assembly is configured to limit the axial position of the bearing relative to the rotating shaft.

In some embodiments, the shaft includes:

the first step;

a radial fitting section, located at one axial end of the first step; the bearing is sleeved on the outside of the radial fitting section, and one axial side of the bearing is abutted by the first step; and

a second step located at an axial end of the radial fitting section away from the first step;

Wherein, the radial dimensions of the first step, the radial fitting section and the second step gradually decrease.

In some embodiments, the axial protection stop ring is installed on the second step, and blocks the other axial end of the bearing.

In some embodiments, the axial protection stop ring includes:

a radially outer shaft extension section abutting against the other axial end of the bearing;

The connection section is fixedly connected with the radially outer shaft extension section, and the radially outer shaft extension section is located radially outside the connection section; the connection section includes a second through hole passing through its axial direction; the A second step passes through the second through hole; wherein, the radially outer shaft extension section protrudes from the connecting section in the axial direction of the bearing; and

The radially inner shaft extension section is fixedly connected to the connecting section, and the radially inner shaft extension section is located at the other axial end of the connecting section away from the radially outer shaft extension section.

In some embodiments, the connection section is screwed to the second step.

In some embodiments, the shaft assembly also includes:

The gap adjustment element is sleeved on the outside of the second step; the gap adjustment element is sandwiched between the radial matching section and the axial protection retaining ring.

In some embodiments, the gap adjustment element includes:

The ring body is sleeved on the outside of the second step.

In some embodiments, along the circumferential direction of the ring body, some areas of the ring body are provided with corrugated sections; or, the ring bodies are all corrugated.

In some embodiments, the protective collar includes a sleeve, and the sleeve is sleeved on the circumferential outer side of the radial matching section;

The axial protection stop ring includes a positioning flange; the sleeve and the positioning flange are fixedly connected or integrated; the radial dimension of the positioning flange is larger than the radial dimension of the sleeve, and the The positioning flange is located on a side of the sleeve away from the first step.

In some embodiments, the shaft assembly also includes:

A locking nut is located on the side of the protective collar away from the first step; the locking nut is fixedly mounted on the rotating shaft; the locking nut cooperates with the first step to define Axial position of the protective collar.

In some embodiments, wherein said protective collar comprises:

The positioning section is sleeved on the outside of the radial fitting section, and is transition-fit or interference-fit with the radial fitting section; and

The threaded connection section is threadedly connected with the second step.

In some embodiments, the inner wall of the protection ring is provided with a deformation groove extending along the circumference of the protection ring.

In some embodiments, there are multiple deformation grooves, and the multiple deformation grooves are distributed along the axial direction of the protective ring.

In some embodiments, wherein there are multiple deformation grooves, the multiple deformation grooves are arranged continuously along the axial direction to form a spiral groove.

In some embodiments, the bearings include: rolling bearings or rings.

The disclosure provides a rotating shaft assembly, including a rotor assembly and a bearing. The rotor assembly includes a rotating shaft. One end of the rotating shaft has a first step. The bearing is sleeved on the rotating shaft. The side of the bearing away from the first step is provided with a protective ring. The protective sleeve The ring includes a sleeve and a positioning flange arranged at one end of the sleeve. The bearing is sleeved outside the sleeve. The positioning flange is located at the end of the bearing away from the first step and cooperates with the first step to limit the axial displacement of the bearing.

In some embodiments, the protective collar is shrink-fitted on the shaft.

In some embodiments, a locking nut is provided on the side of the protective collar away from the first step, and the locking nut is fixedly arranged on the rotating shaft and cooperates with the first step to define the axial position of the protective collar.

In some embodiments, the inner peripheral side of the protective collar includes a positioning section and a threaded connection section, the rotating shaft includes a radial fitting section, the first step is located at the first end of the radial fitting section, and the second end of the radial fitting section is set There is a second step, the positioning section is sleeved on the radial fitting section, and is transition-fitted or interference-fitted with the radial fitting section, and the threaded connection section is threadedly connected with the small-diameter section of the second step.

In some embodiments, the bearing cooperates with the sleeve to form a radial protection structure.

In some embodiments, the bearings are rolling bearings or collars supported by abradable material.

In some embodiments, deformation grooves are provided on the inner wall of the protective collar.

In some embodiments, there are multiple deformation grooves, and the multiple deformation grooves are arranged along the axial direction of the protective ferrule.

In some embodiments, the deformation grooves are arranged continuously along the axial direction, forming a spiral groove.

In some embodiments, the deformation grooves extend along the circumferential direction of the protective ring, and a plurality of deformation grooves are arranged at intervals along the axial direction of the protective ring.

According to another aspect of the present disclosure, a magnetic levitation compressor is provided, including a rotating shaft assembly, which is the above-mentioned rotating shaft assembly.

The rotating shaft assembly provided by the present disclosure includes a rotor assembly and a bearing. The rotor assembly includes a rotating shaft. One end of the rotating shaft has a first step. The bearing is sleeved on the rotating shaft. The side of the bearing away from the first step is provided with a protective ring. The protective ring It includes a sleeve and a positioning flange arranged at one end of the sleeve. The bearing is sleeved outside the sleeve. The positioning flange is located at the end of the bearing away from the first step and cooperates with the first step to limit the axial displacement of the bearing. The rotating shaft assembly can use the protection ring to cooperate with the first step to limit the axial displacement of the rotating shaft, so that the protection ring and the first step can be used to limit the axial displacement of the rotating shaft and form an effective protection for the axial magnetic suspension bearing. , to avoid damage to the axial magnetic suspension bearing.

Description of drawings

Fig. 1 is a schematic structural diagram of a rotating shaft assembly provided by some embodiments of the present disclosure.

Fig. 2 is a schematic structural diagram of an axial protection stop ring of a rotating shaft assembly provided by some embodiments of the present disclosure.

Fig. 3 is a schematic structural diagram of a rotating shaft assembly provided by other embodiments of the present disclosure.

Fig. 4 is a schematic three-dimensional structure diagram of a first type of clearance adjustment element of a shaft assembly provided by some embodiments of the present disclosure.

Fig. 5 is a schematic structural diagram of a second gap adjusting element of a rotating shaft assembly provided by some embodiments of the present disclosure.

Fig. 6 is a schematic diagram of a partial three-dimensional structure of a second gap adjusting element of a rotating shaft assembly provided by some embodiments of the present disclosure.

Fig. 7 is a schematic structural diagram of a rotating shaft assembly provided by some other embodiments of the present disclosure.

Fig. 8 is a schematic structural view of a protective collar of a rotating shaft assembly provided by some embodiments of the present disclosure.

Fig. 9 is a schematic structural diagram of a protective collar of a rotating shaft assembly provided by other embodiments of the present disclosure.

Reference signs:

1. Rotating shaft; 2. The first step; 3. Bearing; 4. Axial protection stop ring; 5. Radial screw hole; 6. Radial fitting section; 7. Second step; 8. Radial outer shaft extension section 9. Connecting section; 10. Protective ring; 11. Sleeve; 12. Locating flange; 13. Lock nut; 14. Radial inner shaft extension section; 15. Gap adjustment element;

101, positioning section; 102, threaded connection section;

100. Rotor assembly.

Detailed ways

As shown in conjunction with FIGS. 1 to 9 , an embodiment of the present disclosure provides a rotating shaft assembly.

Referring to FIG. 1 to FIG. 2 , an embodiment of the present invention provides a rotating shaft assembly, including a rotor assembly 100 , a bearing 3 , a protection ring 10 and an axial protection stop ring 4 . The rotor assembly 100 includes a rotating shaft 1 . The bearing 3 includes a first through hole 30 extending axially through itself. In some embodiments, the bearing 3 includes a rolling bearing or a ring, and the following description will be made by taking the rolling bearing as an example of the bearing 3 . The rotating shaft 1 passes through the first through hole 30 . The protective ring 10 is interposed between the rotating shaft 1 and the bearing 3 . The axial protection retaining ring 4 is configured to limit the axial position of the bearing 3 relative to the rotating shaft 1 .

The rotor assembly 100 includes a rotating shaft 1, driven by a driving component (not shown in the figure), the rotating shaft 1 rotates around its own axis. The rotating shaft 1 has no displacement in its own axial direction.

In some embodiments, the rotating shaft 1 includes a first step 2 , a radial matching section 6 and a second step 7 . The radial fitting section 6 is located at one axial end of the first step 2 ; the bearing 3 is sheathed on the outside of the radial fitting section 6 , and one axial side of the bearing 3 is abutted by the first step 2 . The second step 7 is located at the axial end of the radial fitting section 6 away from the first step 2 . Wherein, the radial dimensions of the first step 2 , the radial fitting section 6 and the second step 7 gradually decrease.

Rotating shaft 1 adopts a stepped shaft structure, which has multiple shaft sections of different sizes, and can use the variable diameter of each shaft section to assist other components to achieve installation and positioning, so as to reduce the number of parts used for axial positioning and reduce the number of parts. The problem of poor assembly accuracy caused by the accumulation of tolerances reduces the number of parts and reduces the cost of parts.

The axial protection stop ring 4 is used to realize the axial limit of the bearing 3 and prevent the bearing 3 from moving relative to the rotating shaft 1 along the axial direction of the rotating shaft 1 . There are many ways to implement the axial protection stop ring 4 , such as realizing the axial limit of the bearing 3 through its own structure, or cooperating with other components to realize the axial limit of the bearing 3 .

In some embodiments, the axial protection stop ring 4 is installed on the second step 7 , and the axial protection stop ring 4 blocks the other axial end of the bearing 3 .

The rotating shaft 1 adopts a stepped shaft, so the first step 2 plays a role in positioning the axial end of the bearing 3; the axial protection stop ring 4 plays a role in positioning the other axial end of the bearing 3, so that the two Both ends are positioned, and the axial position of the bearing 3 is determined.

Referring to FIG. 1 to FIG. 2 , in some embodiments, the axial protection stop ring 4 includes a radially outer shaft extension section 8 , a connecting section 9 and a radially inner shaft extension section 14 . The radially outer shaft extension section 8 abuts against the other axial end of the bearing 3 . The connecting section 9 is fixedly connected with the radially outer shaft extension section 8 , and the radially outer shaft extension section 8 is located at one axial end of the connecting section 9 . The connecting section 9 includes a second through hole 90 extending axially through itself. The second step 7 passes through the second through hole 90 . Wherein, the radially outer shaft extension section 8 protrudes from the connecting section 9 in the axial direction of the bearing 3 . The radially inner shaft extension section 14 is fixedly connected to the connecting section 9 , and the radially inner shaft extension section 14 is located at the other axial end of the connecting section 9 away from the radially outer shaft extension section 8 .

The radially outer shaft extension section 8 , the connecting section 9 and the radially inner shaft extension section 14 are integrated, or the three are fixedly connected by means of bolts or welding. In the axial direction of the bearing 3, the radially outer shaft extension section 8 protrudes toward the bearing 3 relative to the connecting section 9, so that when there is a certain distance between the connecting section 9 and the bearing 3, the radially outer shaft extension section 8 has already against the bearing 3.

There is no requirement on the axial and radial dimensions of the radially inner shaft extension section 14 , which is sheathed outside the circumference of the second step 7 . The radial inner shaft extension section 14 is used for setting the radial screw holes 5 . The axial direction of the radial screw hole 5 is parallel to the radial direction of the bearing 3 . Screws (not shown in the figure) are installed in the radial screw holes 5 to fix the axial protection stop ring 4 in the radial direction of the bearing 3, and the axial protection stop ring 4 is locked by screws to increase the axial protection stop ring 4 and the frictional force of the rotating shaft 1 improves the reliability of the axial positioning of the axial protection retaining ring 4.

In some embodiments, the connecting section 9 is screwed to the second step 7 . The inner wall of the second through hole 90 of the connecting section 9 is provided with internal threads, and the second step 7 is correspondingly provided with external threads, and the connecting section 9 and the second step 7 are locked by threads. Moreover, the length of the threaded connection between the connecting section 9 and the second step 7 is controllable and adjustable, so as to realize the adjustment of the axial positioning position of the bearing 3 .

The connecting section 9 is screwed to the second step 7 to realize the axial positioning of the axial protection stop ring 4 and the rotating shaft 1 , thereby ensuring the axial positioning accuracy between the axial protection stop ring and the first step 2 . The thread fit between the axial protection retaining ring 4 and the rotating shaft 1 is a fine thread, so that the thread structure is used for self-locking to prevent loosening and avoid displacement of the axial protection retaining ring 4 during the working process.

Referring to FIG. 3 , in some embodiments, the shaft assembly further includes a gap adjusting element 15 , and the gap adjusting element 15 is sleeved on the outside of the second step 7 . The gap adjusting element 15 is interposed between the radial fitting section 6 and the axial protection retaining ring 4 .

The gap adjustment element 15 is used to adjust the axial distance between the radial fitting section 6 and the axial protection stop ring 4, and then adjust the position where the radially outer shaft extension section 8 of the axial protection stop ring 4 abuts against the bearing 3, so as to achieve alignment Adjustment of the axial positioning position of the bearing 3.

Referring to FIG. 4 , in some embodiments, the gap adjustment element 15 includes a ring body 151 sleeved on the outside of the second step 7 . The maximum outer diameter of the ring body 151 is smaller than the through hole size of the radially outer shaft extension section 8 , and the ring body 151 is located in the through hole of the radially outer shaft extension section 8 .

Referring to FIG. 5 , in some embodiments, along the circumferential direction of the ring body 151 , part of the ring body 151 is provided with corrugated segments 152 .

Referring to FIG. 6 , along the circumferential direction of the ring body 151 , the ring body 151 is entirely corrugated. The circumferential direction of the ring body 151 is not flat, but undulating. Through the deformation of the ring body 151 , the position of the radially outer shaft extension section 8 is adjusted so as to limit the axial position of the bearing 3 .

Referring to Fig. 3, the radial gap X formed between the bearing 3 and the rotor assembly 100 is the smallest radial gap in the overall compressor, and the radial gap is used to reduce or even prevent the magnetic bearing, motor or impeller from colliding with the stator, Play a role of radial protection. The end surface of the axial protection retaining ring 4 close to the bearing 3 and the step surface of the first step 2 of the rotor assembly 100 form an axial gap Z, and the difference Z-Y between it and the width Y of the bearing 3 is the smallest axis in the overall compressor. To the gap, play the role of axial protection.

Referring to Fig. 7 and Fig. 8, in some embodiments, the protective collar 10 includes a sleeve 11, and the sleeve 11 is sleeved on the circumferential outside of the radially mating section 6. The axial protection stop ring 4 includes a positioning flange 12; the sleeve 11 and the positioning flange 12 are fixedly connected or integrated. The inner diameters of the respective holes of the sleeve 11 and the positioning flange 12 are the same, or the radial size of the hole of the sleeve 11 is larger than the radial size of the hole of the positioning flange 12 . The maximum radial dimension of the positioning flange 12 is greater than the maximum radial dimension of the sleeve 11 , and the positioning flange 12 is located on a side of the sleeve 11 away from the first step 2 . The positioning flange 12 protrudes from the sleeve 11 , so the positioning flange 12 acts as a position limiter for the other axial end of the bearing 3 .

Referring to FIG. 7 , in some embodiments, the shaft assembly further includes a locking nut 13 , and the locking nut 13 is located on the side of the protective collar 10 away from the first step 2 . The locking nut 13 is fixedly installed on the rotating shaft 1 ; the locking nut 13 cooperates with the first step 2 to limit the axial position of the protective collar 10 . The locking nut 13 is used to abut against the protection ring 10 to determine the axial position of the protection ring 10 . The locking nut 13 is threadedly connected with the rotating shaft 1 , and the axial fixing of the protective collar 10 is realized by torque locking the locking nut 13 .

Referring to FIG. 7 , in some embodiments, the protective collar 10 includes a positioning section 101 and a threaded connection section 102 . The positioning section 101 is sheathed on the outside of the radial fitting section 6 and is transition-fitted or interference-fitted with the radial fitting section 6 . The threaded connection section 102 is threaded with the second step 7 .

The protective collar 10 and the locking nut 13 are integrated, or two separate parts.

Referring to Fig. 7, the radial gap X2 between the outer wall surface of the sleeve 11 and the inner wall surface of the bearing 3 is the smallest radial gap in the overall compressor, and this gap avoids the magnetic suspension bearing, the motor or the impeller, etc. from colliding with the stator. Play a role of radial protection. The distance between the end surface of the positioning flange 12 facing the bearing 3 and the end surface of the first step 2 facing the bearing 3 is Z2, and the width of the bearing 3 is Y2. The difference between Z2-Y2 is the smallest axial clearance in the overall compressor, which acts as an axial protection.

Referring to FIG. 9 , in some embodiments, the inner wall of the protective collar 10 is provided with a deformation groove 16 extending along the circumferential direction of the protective collar 10 . The cross-section of the deformation groove 16 may be V-shaped, or rectangular, semi-circular, semi-elliptical or trapezoidal. When the rotor assembly 100 falls into contact with the protective collar 10 , the protective collar 10 utilizes the elastic deformation of the deformation groove 16 to absorb part of the impact energy and reduce the impact of the rotor.

Referring to FIG. 9 , in some embodiments, there are multiple deformation grooves 16 , and the multiple deformation grooves 16 are distributed along the axial direction of the protective ring 10 .

In some embodiments, there are multiple deformation grooves 16, and the multiple deformation grooves 16 are arranged continuously along the axial direction to form a spiral groove.

Referring to Fig. 1 to Fig. 9, some other embodiments are introduced below.

The shaft assembly includes a rotor assembly 100 and a bearing 3 . The rotor assembly 100 includes a rotating shaft 1. One end of the rotating shaft 1 has a first step 2. A bearing 3 is sleeved on the rotating shaft 1. An axial protection stop ring 4 is provided on the side of the bearing 3 away from the first step 2. The bearing 3 is located on the first step. Between the step 2 and the axial protection retaining ring 4.

The rotating shaft assembly can use the axial protection retaining ring 4 to cooperate with the first step 2 to limit the axial displacement of the rotating shaft 1, so that the axial protection retaining ring 4 and the first step 2 can be used to limit the axial displacement of the rotating shaft 1. The position can effectively protect the axial magnetic suspension bearing and avoid damage to the axial magnetic suspension bearing.

In some embodiments, the axial protection retaining ring 4 is configured as a ring, and the axial protection retaining ring 4 is fixedly arranged on the side of the bearing 3 away from the first step 2 . In some embodiments, the axial protection retaining ring 4 cooperates with the first step 2 to limit the axial displacement of the bearing 3 from both sides of the bearing 3. By limiting the axial displacement of the bearing 3, the The effect of protecting the above-mentioned bearing 3 .

In some embodiments, the axial protection retaining ring 4 has an internal thread, the rotating shaft 1 has an external thread, and the axial protection retaining ring is screwed to the external thread of the rotating shaft 1 through the internal thread. The axial protection retaining ring 4 is threadedly connected to the rotating shaft 1 to realize the axial positioning of the axial protecting retaining ring and the rotating shaft 1 , thereby ensuring the axial positioning accuracy between the axial protecting retaining ring and the first step 2 . In some embodiments, in order to avoid displacement of the axial protection retaining ring 4 during the working process, the thread fit between the axial protection retaining ring 4 and the rotating shaft 1 can be a fine thread, so that the thread structure can be used for self-locking to prevent Loosening occurs.

In some embodiments, the axial protection retaining ring 4 is provided with radial screw holes 5 in the radial direction, and the axial protection retaining ring 4 is axially positioned by radial bolts disposed in the radial screw holes 5 . In some embodiments, while the axial protection retaining ring 4 is threadedly connected to the rotating shaft 1, the radial bolts in the radial screw holes 5 are used to further axially position the axial protection retaining ring 4, and the radial Locking the bolts increases the frictional force between the axial protection retaining ring and the thread on the rotating shaft 1, improving the reliability of axial positioning. In some embodiments, there are at least two radial screw holes 5 , and each radial screw hole 5 is evenly distributed along the circumferential direction of the axial protection stop ring, so as to achieve a better axial locking effect. The number of radial screw holes 5 is generally 3 or 4.

In some embodiments, the rotating shaft 1 includes a radial fitting section 6, the bearing 3 is sleeved on the radial fitting section 6, and cooperates with the radial fitting section 6 to form a radial protection structure, and the first step 2 is located in the radial fitting section At the first end of 6, the axial protection retaining ring is located at the second end of the radial fitting section 6. In some embodiments, the machining accuracy of the radial fitting section 6 is higher than that of other parts of the rotating shaft 1, so that the radial fitting section 6 and the bearing 3 form a more precise radial fit, so as to effectively carry out the radial magnetic suspension bearing. Protect.

The rotating shaft assembly realizes positioning in the radial direction and the axial direction of the rotating shaft 1 at the same time, so the axial length of the rotating shaft 1 is effectively shortened, the deflection of the rotating shaft 1 is reduced, the volume of the whole machine is reduced, and the cost is reduced.

In some embodiments, the second end of the radial fitting section 6 is provided with a second step 7 . The axial protection stop ring 4 includes a radially outer shaft extension section 8, a connecting section 9 and a radially inner shaft extension section 14 arranged in sequence in the axial direction, the radially outer shaft extension section 8 is located on the circumferential outer side of the radial fitting section 6, And cooperate with the first step 2 to jointly limit the axial displacement of the bearing 3, the connecting section 9 abuts against the step surface of the second step 7, the radially inner shaft extension section 14 is sleeved on the second step 7, and is connected with the second step 7 Step 7 is fixedly connected.

In some embodiments, the end surface of the radially outer shaft extension section 8 is one of the axial positioning surfaces of the bearing 3 , and the positioning surface cooperates with the first step 2 to jointly limit the axial displacement of the bearing 3 . The radially outer shaft extension section 8 is located on the circumferential outer side of the radially outer shaft extension section 6, and the bearing 3 and the first step 2 and the radially outer shaft extension section are adjusted by adjusting the axial extension length of the radially outer shaft extension section 8 8 to meet the installation requirements of axial bearings of different specifications.

The end face of the connecting section 9 facing the radial fitting section 6 is the axial positioning end face between the axial protection retaining ring and the rotating shaft 1, which defines the axial displacement position of the axial protecting retaining ring on the rotating shaft 1, by defining the connecting section The distance between the mating end surface of 9 and the positioning end surface of the radially outer shaft extension section 8 can effectively ensure the axial positioning precision of the axial protection stop ring 4 to the bearing 3 .

In some embodiments, the bearing 3 is a rolling bearing or a collar supported by a wear-resistant material.

In some embodiments, the rotor assembly 100 includes a rotating shaft 1 , a bearing 3 and an axial protection retaining ring 4 , the bearing 3 is directly or indirectly fixed to the housing, and the bearing 3 is a rolling bearing or a ring made of wear-resistant material.

The radial gap X1 formed between the bearing 3 and the rotor assembly 100 is the smallest radial gap in the overall compressor. Protective effects. An axial clearance Z1 is formed between the first end surface of the axial protection retaining ring and the step surface of the first step 2 of the rotor assembly 100, and the difference Z1-Y1 between it and the width Y1 of the bearing 3 is the smallest in the overall compressor The axial clearance plays the role of axial protection.

The axial protection retaining ring is connected with the rotor assembly 100 through threads, and the adjustment of the axial gap Z1 is realized through the threads. At the same time, n screws are evenly distributed in the circumferential direction of the axial protection retaining ring. By locking these screws, the thread on the shaft 1 is increased. The frictional force, with thread to ensure the fixation of the axial position of the axial protection retaining ring, n is 3 or 4. The adjustment range of the axial gap Z1 can be expanded by increasing the distance between the axial positioning surface of the radially outer shaft extension section 8 of the axial protection stop ring and the axial positioning surface of the connecting section 9 .

The rotating shaft assembly realizes radial and axial protection, and at the same time does not need to replace or reprocess parts, and the adjustment of the axial protection gap can be realized through assembly, so the structure is simple, the structural modification of the magnetic levitation compressor is small, and the cost is low .

In some embodiments, the second end of the radial fitting section 6 is provided with a second step 7, and a gap adjustment element 15 is arranged between the axial protection stop ring 4 and the second step 7, and the gap adjustment element 15 can adjust the axial Protect the axial gap between the retaining ring 4 and the second step 7 .

In some embodiments, the axial protection retaining ring 4 includes a radially outer shaft extension section 8 , a connecting section 9 and a radially inner shaft extension section 14 arranged in sequence in the axial direction. The radial outer shaft extension section 8 is sleeved outside the radial matching section 6, and cooperates with the first step 2 to limit the axial displacement of the bearing 3, and the radial inner shaft extension section 14 is sleeved on the small diameter section of the second step 7 and threaded connection between the small diameter section, the gap adjustment element 15 is arranged between the connection section 9 and the second step 7, one end of the gap adjustment element 15 is in contact with the step surface of the radial fitting section 6, and the other end is in contact with the connection section 9 end face contacts. The gap adjustment element 15 is an elastic member, and the adjustment of the axial gap Z is realized through the compression of the gap adjustment element 15 and the screw connection between the radially inner shaft extension section 14 and the second step 7 .

In some embodiments, the gap adjustment element 15 is a metal rubber ring or a corrugated spring washer. The metal rubber ring is a ring structure made of metal rubber material, and the corrugated spring pad is a ring structure made of spring steel. There are several corrugated structures on the ring, and the corrugated structure can be used to achieve elastic deformation.

In some embodiments, the protective collar 10 includes a sleeve 11 and a positioning flange 12 disposed at one end of the sleeve 11, the bearing 3 is sleeved outside the sleeve 11, and the positioning flange 12 is located on the bearing 3 away from the first step 2 One end, and cooperate with the first step 2 to limit the axial displacement of the bearing 3.

In some embodiments, the sleeve 11 of the protective collar 10 is sleeved on the outside of the rotating shaft 1, the positioning flange 12 is integrally formed with the sleeve 11, and the end surface of the positioning flange 12 facing the first step 2 is matched with the first step 2, An axial limit is formed for the bearing 3, and the effect of protecting the axial bearing is achieved by limiting the axial displacement of the bearing 3.

In some embodiments, the protective collar 10 is fixed on the outer periphery of the rotating shaft 1 by means of a heat fit. The protective ring 10 is interference-fitted with the rotating shaft 1 by means of shrink fit, so that the protective ring 10 is fixedly connected with the rotating shaft 1 .

In some embodiments, a locking nut 13 is provided on the side of the protective collar 10 away from the first step 2 , and the locking nut 13 is fixedly arranged on the rotating shaft 1 and jointly defines the protective collar 10 with the first step 2 axial position. In some embodiments, the locking nut 13 is screwed to the rotating shaft 1 to lock the axial position of the protection ring 10 , so as to realize the axial limit of the protection ring 10 on the bearing 3 .

In some embodiments, the protective collar 10 and the locking nut 13 are provided separately, and the protective collar 10 is transition-fitted with the rotating shaft 1 , or fitted with a small clearance, or fitted with a small interference. A small clearance fit means that the clearance fit between the protective ring 10 and the rotating shaft 1 is a minimum clearance fit, and a small interference fit means that the interference fit between the protective ring 10 and the rotating shaft 1 is a minimum interference fit. With the above technical solution, the radial fit precision between the protective collar 10 and the rotating shaft 1 is high, and at the same time, it reduces or even prevents the locking of the rotating shaft 1 and the protective collar 10 , making it difficult to disassemble the protective collar 10 from the rotating shaft 1 .

In some embodiments, the locking nut 13 and the protective ferrule 10 are arranged separately, so that the functions of the two are separated, and each realizes a single function, which reduces the overall processing difficulty of the parts and effectively improves the processing accuracy of the protective ferrule 10 , reduce the thread fit precision of the locking nut 13, thereby reducing the processing cost as a whole and improving the processing efficiency.

In some embodiments, the rotating shaft 1 includes a radial fitting section 6 , the first step 2 is located at a first end of the radial fitting section 6 , and the second end of the radial fitting section 6 is provided with a second step 7 . The axial length of the protective collar 10 is greater than the axial length of the radial fitting section 6 , so as to realize the axial positioning effect of the lock nut 13 on the protective collar 10 .

In some embodiments, the inner wall of the protective collar 10 includes a positioning section 101 and a threaded connection section 102 . The rotating shaft 1 includes a radial fitting section 6, the first step 2 is located at the first end of the radial fitting section 6, the second end of the radial fitting section 6 is provided with a second step 7, and the positioning section 101 is sleeved on the radial fitting section 6, and transition fit or interference fit with the radial fit section 6. The threaded connection section 102 is threaded with the second step 7 .

In some embodiments, the protective collar 10 and the locking nut 13 are of an integral structure, forming an integrated protective collar 10 .

In some embodiments, the sleeve 11 positions and limits the bearing 3 in the radial direction. The above technical solution has both radial positioning and axial positioning, so the axial length of the rotating shaft 1 is effectively shortened, the deflection of the rotating shaft 1 is reduced, the volume of the whole machine is reduced, and the cost is reduced.

In some embodiments, the rotating shaft assembly includes a rotating shaft 1 , a bearing 3 and an axial protection stop ring 4 . The bearing 3 is directly or indirectly fixed to the housing, and may be a rolling bearing or a collar made of wear-resistant material. The protective ring 10 is sleeved on the rotating shaft 1 of the rotor assembly 100, and the radial gap X2 formed between the cylindrical surface of the protective ring 10 and the bearing 3 is the smallest radial gap in the overall compressor, which prevents magnetic bearings, motors or The impeller, etc. rubs against the stator, which plays a role of radial protection. A gap Z2 is formed between the end surface of the protective ring 10 and the step surface of the first step of the rotor assembly 100, and the difference Z2-Y2 between the gap Z2 and the width Y2 of the bearing 3 is the smallest axial gap in the overall compressor, which plays a role in Axial protection. The protective collar 10 abuts against the locking nut 13 , and the locking nut 13 is threadedly connected with the rotating shaft 1 , and the locking nut 13 is torque-locked to achieve axial fixation.

The above technical solution directly limits one of the end faces of the bearing 3 through the first step 2, which is equivalent to reducing one assembly part, reducing the assembly accuracy error caused by the accumulation of part tolerances, and reducing the number of parts , reducing parts cost.

In some embodiments, a deformation groove 16 is provided on the inner wall of the protective collar 10 . There can be multiple deformation grooves 16, and each deformation groove 16 extends along the circumferential direction of the protective collar 10 to form an annular groove. A plurality of deformation grooves 16 are arranged at intervals along the axial direction of the protective collar 10, and the deformation grooves 16 can also be arranged along the axial direction of the protective collar 10. Axially continuously arranged to form a helical groove extending axially along the inner wall. The cross-section of the deformation groove 16 may be V-shaped, or rectangular, semi-circular, semi-elliptical or trapezoidal. When the rotor assembly 100 falls to the protective collar 10, the protective collar 10 utilizes the elastic deformation of the deformation groove 16 to absorb part of the impact energy, thereby reducing the rotor drop impact.

In some embodiments, the protection ring 10 is a damping metal material, such as Cu-Mn alloy, Cu-Mn-Al alloy, Al-Zn alloy, Mg-Zr alloy and other high damping metal materials.

In the above technical solution, the first step 2 of the rotating shaft 1 is used to form an axial stop, thereby reducing the number of parts used for axial positioning, thereby reducing the problem of poor assembly accuracy caused by the accumulation of part tolerances. At the same time, the protective collar 10 is made of damping alloy material, and the inner peripheral surface is provided with deformation grooves 16 , which can more effectively reduce the impact of the rotor assembly 100 falling and protect the rotor assembly 100 .

According to some embodiments of the present disclosure, the magnetic levitation compressor includes the rotating shaft assembly disclosed in any technical solution of the present disclosure.

In describing the present disclosure, it is to be understood that the terms "central", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", The orientations or positional relationships indicated by "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying References to devices or elements must have a specific orientation, be constructed and operate in a specific orientation and therefore should not be construed as limiting the scope of the present disclosure.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present disclosure and not to limit them; although the present disclosure has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: the present disclosure can still be Modifications are made to the disclosed specific implementation methods or equivalent replacements are made to some technical features; without departing from the spirit of the technical solutions of the present disclosure, all of them shall be covered by the scope of the technical solutions claimed in the present disclosure.

Claims

A shaft assembly, comprising:

A rotor assembly (100), including a shaft (1);

The bearing (3) includes a first through hole (30) passing through its axial direction; the rotating shaft (1) passes through the first through hole (30);

a protective collar (10), interposed between the rotating shaft (1) and the inner wall of the first through hole (30); and

The axial protection retaining ring (4) is configured to limit the axial position of the bearing (3) relative to the rotating shaft (1).
The shaft assembly according to claim 1, wherein the shaft (1) comprises:

first step (2);

The radial fitting section (6) is located at one axial end of the first step (2); the bearing (3) is sleeved on the outside of the radial fitting section (6), and the bearing (3) One axial side is abutted by the first step (2); and

The second step (7) is located at an axial end of the radial fitting section (6) away from the first step (2);

Wherein, the radial dimensions of the first step (2), the radial fitting section (6) and the second step (7) gradually decrease.
The rotating shaft assembly according to claim 2, wherein the axial protection retaining ring (4) is installed on the second step (7), and blocks the other axial end of the bearing (3).
The rotating shaft assembly according to claim 3, wherein the axial protection retaining ring (4) comprises:

The radially outer shaft extension section (8) abuts against the other axial end of the bearing (3);

The connection section (9) is fixedly connected with the radially outer shaft extension section (8), and the radially outer shaft extension section (8) is located radially outside the connection section (9); the connection section ( 9) includes a second through hole (90) running through its own axial direction; the second step (7) passes through the second through hole (90); wherein, the radially outer shaft extension section (8) is The axial direction of the bearing (3) protrudes from the connecting section (9); and

The radially inner shaft extension section (14) is fixedly connected to the connecting section (9), and the radially inner shaft extension section (14) is located away from the radially outer shaft extension section from the connecting section (9) (8) the axial other end.
The shaft assembly according to claim 4, wherein the connecting section (9) is threadedly connected to the second step (7).
The shaft assembly according to any one of claims 3-5, further comprising:

The gap adjustment element (15) is sleeved on the outside of the second step (7); the gap adjustment element (15) is sandwiched between the radial fitting section (6) and the axial protection retaining ring ( 4) Between.
The shaft assembly according to claim 6, wherein the gap adjustment element (15) comprises:

The ring body (151) is sleeved on the outside of the second step (7).
The rotating shaft assembly according to claim 7, wherein along the circumferential direction of the ring body (151), corrugated sections (152) are provided in part of the ring body (151); or, the ring body ( 151) are corrugated.
The rotating shaft assembly according to claim 3, wherein the protective collar (10) comprises a sleeve (11), and the sleeve (11) is sleeved on the circumferential outer side of the radial fitting section (6);

The axial protection stop ring (4) includes a positioning flange (12); the sleeve (11) and the positioning flange (12) are fixedly connected or integrated; the positioning flange (12) The radial dimension is larger than the radial dimension of the sleeve (11), and the positioning flange (12) is located on the side of the sleeve (11) away from the first step (2).
The shaft assembly of claim 9, further comprising:

A locking nut (13), located on the side of the protective collar (10) away from the first step (2); the locking nut (13) is fixedly mounted on the rotating shaft (1); The locking nut (13) cooperates with the first step (2) to limit the axial position of the protective collar (10).
The shaft assembly according to claim 9, wherein the protective collar (10) comprises:

a positioning section (101), sleeved on the outside of the radial fitting section (6), and transition-fit or interference-fit with the radial fitting section (6); and

The threaded connection section (102) is threadedly connected with the second step (7).
The rotating shaft assembly according to any one of claims 1-11, wherein the inner wall of the protective collar (10) is provided with a deformation groove (16) extending along the circumferential direction of the protective collar (10).
The rotating shaft assembly according to claim 12, wherein there are multiple deformation grooves (16), and the multiple deformation grooves (16) are distributed along the axial direction of the protective ring (10).
The rotating shaft assembly according to claim 12, wherein there are a plurality of deformation grooves (16), and the plurality of deformation grooves (16) are arranged continuously along the axial direction to form a spiral groove.
The rotating shaft assembly according to any one of claims 1-14, wherein the bearing (3) comprises: a rolling bearing or a collar.
A magnetic levitation compressor, comprising the rotating shaft assembly according to any one of claims 1-15.