Rotating assembly and compressor

Abstract

The invention relates to a rotating assembly and a compressor, the rotating assembly comprises a rotating piece, a mass block and a connecting piece, the connecting piece extends to penetrate through the mass block so as to fix the mass block to the rotating piece, the rotating assembly is characterized in that the connecting piece comprises a head part and a body extending from the head part in the axial direction of the connecting piece, and the head part is provided with a through hole; the head has a distal end remote from the body and a proximal end connected to the body, the head including a portion that tapers in a direction from the distal end toward the proximal end. According to the rotating assembly, the fatigue strength of the rotating assembly can be improved, and the service life of the rotating assembly is prolonged.

Description

Technical Field

[0001] The present invention relates to a rotating assembly and a compressor including the rotating assembly. Background Art

[0002] The content of this section only provides background information related to the present invention, which may not constitute prior art.

[0003] A compressor (e.g., a scroll compressor) generally drives a compression member to move by the rotation of a rotor assembly, thereby compressing a working fluid. To balance the generated unbalance and reduce vibration or noise, a mass block is usually installed on the rotor.

[0004] During the operation of the compressor, the mass block rotates with the rotor, thereby generating centrifugal force and other non-axial forces. In the case of high-speed operation of the compressor, etc., very large acting forces are generated, which act on the connecting member that fixes the mass block and the rotating member, making the connecting member prone to fatigue fracture, and further causing the fixation of the mass block and the rotating member to become loose, and even causing the mass block to separate from the rotating member.

[0005] Therefore, there is a need to provide an improved rotating assembly and compressor. Summary of the Invention

[0006] An object of one or more embodiments of the present invention is to improve the fatigue strength of the rotating assembly and extend the service life of the rotating assembly.

[0007] Another object of one or more embodiments of the present invention is to improve the fatigue strength of the rotating assembly in a simple and easy-to-process manner.

[0008] According to one aspect of the present invention, there is provided a rotating assembly, which includes: a rotating member, a mass block, and a connecting member. The connecting member extends through the mass block to fix the mass block to the rotating member. It is characterized in that the connecting member includes a head and a body extending axially from the head. The head has a distal end away from the body and a proximal end connected to the body. The head includes a portion that tapers in a direction from the distal end towards the proximal end.

[0009] According to one aspect of the present invention, the rotating member is a rotor.

[0010] According to one aspect of the present invention, the mass block is a balance block.

[0011] According to one aspect of the present invention, the centroid of the mass block deviates from the rotation axis of the rotating assembly.

[0012] According to one aspect of the present invention, the head includes a top surface formed at the distal end, and a tapered outer peripheral surface exists between the top surface and the body.

[0013] According to one aspect of the present invention, the inclination angle of the tapered outer peripheral surface with respect to the lateral direction of the connecting member is in the range of 20 degrees to 60 degrees, and the lateral direction is perpendicular to the axial direction.

[0014] According to one aspect of the present invention, the length of the head in the axial direction is in the range of 2 mm to 5 mm.

[0015] According to one aspect of the present invention, the balance weights include a first balance weight provided on a first side of the rotor and a second balance weight provided on a second side of the rotor.

[0016] According to one aspect of the present invention, at least one of the first balance weight and the second balance weight is formed with an orifice, the orifice includes a first section having a tapered aperture diameter and a second section having a uniform aperture diameter, the first section communicates with the second section, and the outer peripheral surface of the head corresponds to the shape of the first section of the orifice.

[0017] According to one aspect of the present invention, the mass of the first balance weight is greater than the mass of the second balance weight, and the orifice is formed in the first balance weight.

[0018] According to one aspect of the present invention, the head of the connecting member is completely sunk into the orifice.

[0019] According to one aspect of the present invention, the connecting member is configured as a rivet.

[0020] According to another aspect of the present invention, a compressor including the above-mentioned rotating assembly is provided.

[0021] In the rotating assembly according to the present invention, by improving the fitting manner of the connecting member in a clever way, fatigue wear / fracture of the connecting member can be prevented, the fatigue strength of the rotating assembly can be improved, and the service life of the rotating assembly can be extended.

[0022] From the following detailed description, other features, advantages and application fields of the present invention will become clearer. It should be understood that these detailed descriptions and specific examples, although showing the preferred embodiments of the present invention, are for the purpose of illustrative explanation only and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Through the following description with reference to the drawings, the features and advantages of one or more embodiments of the present invention will become more readily understood, in the drawings:

[0024] Figure 1 is a cross-sectional view showing a compressor according to the present invention;

[0025] Figure 2 is an exploded perspective view showing a rotating assembly according to a first exemplary embodiment of the present invention;

[0026] Figure 3 is a cross-sectional view showing a rotating assembly according to a first exemplary embodiment of the present invention; and

[0027] Figure 4 is a perspective view showing a rotating assembly according to a second exemplary embodiment of the present invention. Detailed Description of the Invention

[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings.

[0029] Exemplary embodiments are provided so that this invention will be thorough and will fully convey the scope to those skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods to provide a thorough understanding of the various embodiments of the present invention. It will be apparent to those skilled in the art that specific details need not be employed, that the exemplary embodiments may be embodied in many different forms, and that neither should be construed as limiting the scope of the invention. In some exemplary embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0030] First, reference will be made to Figure 1 describe the overall construction and operating principle of a compressor (scroll compressor). As Figure 1 shown, the compressor 1 may include a housing 10, a top cover provided at one end of the housing 10, a bottom cover provided at the other end of the housing 10, and a partition 12 provided between the top cover and the housing 10 to divide the internal space of the compressor into a high-pressure side and a low-pressure side. The space between the partition 12 and the top cover constitutes the high-pressure side, and the space between the partition 12, the housing 10, and the bottom cover constitutes the low-pressure side. A motor is provided in the housing 10, and the motor may include a stator 20 and a rotor. The rotating shaft of the stator and the rotor may drive a compression mechanism composed of a fixed scroll 50 and a moving scroll 60. The moving scroll 60 includes a moving scroll end plate 62, a spiral moving scroll blade 64 formed on one side of the moving scroll end plate, and a hub portion 66 formed on the other side of the moving scroll end plate. The fixed scroll 50 includes a fixed scroll end plate 52, a spiral fixed scroll blade 54 formed on one side of the fixed scroll end plate, and an exhaust port formed at a substantially central position of the fixed scroll end plate. A series of compression chambers are formed between the fixed scroll blade 54 of the fixed scroll 50 and the moving scroll blade 64 of the moving scroll 60, and the volume of the compression chambers gradually decreases when moving from the radially outer side to the radially inner side.

[0031] One end of the rotor shaft 100 is supported by the main bearing housing 40. An eccentric crank pin 112 is provided at one end of the rotor shaft. An unloading bushing is provided between the eccentric crank pin 112 and the hub portion 66 of the moving scroll 60. The unloading bushing can be provided inside the hub portion, and a drive bearing can be provided between the hub portion and the unloading bushing and fixed to the inner wall surface of the hub portion. When the motor is started and driven by the rotor assembly, the moving scroll 60 will perform a translational rotation relative to the fixed scroll 50 (i.e., the central axis of the moving scroll 60 moves around the central axis of the fixed scroll 50, but the moving scroll 60 itself does not rotate around its own central axis) to achieve the compression of the fluid. The fluid compressed by the fixed scroll 50 and the moving scroll 60 is discharged to the high-pressure side through the exhaust port.

[0032] In order to achieve the compression of the fluid, an effective axial seal is required between the fixed scroll 50 and the moving scroll 60. Specifically, axial seals are required between the tips of the fixed scroll blades of the fixed scroll 50 and the moving scroll end plate 62 of the moving scroll 60, and between the tips of the moving scroll blades of the moving scroll 60 and the fixed scroll end plate 52. Generally, a back pressure chamber is provided on the side of the fixed scroll end plate 52 opposite to the fixed scroll blades 54. The back pressure chamber is in fluid communication with the medium pressure chamber through an axially extending through hole (not shown) formed in the end plate, thereby forming a force that presses the fixed scroll 50 against the moving scroll 60. At the same time, the opposite side of the moving scroll 60 is axially supported / thrust by the thrust plate against the moving scroll end plate 62. Therefore, the fixed scroll 50 and the moving scroll member 60 can be effectively pressed together by using the back pressure chamber and the thrust plate.

[0033] The lubrication process of each component in the compressor will be described below. In Figure 1 In the example of the vertical compressor shown, lubricant is stored at the bottom of the compressor housing. Correspondingly, a channel is formed in the rotor shaft 100 that generally extends along its axial direction, that is, a central hole 114 formed at the lower end of the rotor shaft 100 and an eccentric hole 116 that extends upward from the central hole 114 to the end face of the eccentric crank pin 112. The end of the central hole 114 can be immersed in the lubricant at the bottom of the compressor housing or otherwise supplied with lubricant. During the operation of the compressor, one end of the central hole is supplied with lubricant by a lubricant supply device. The lubricant entering the central hole 114 is pumped or thrown into the eccentric hole 116 by the action of centrifugal force during the rotation of the rotor shaft 100 and flows upward along the eccentric hole 116 until it reaches the end face of the eccentric crank pin 112. The lubricant discharged from the end face of the eccentric crank pin 112 flows downward along the gap between the unloading bushing and the eccentric crank pin 112 and the gap between the unloading bushing and the hub portion to reach the recess of the main bearing housing 40. A part of the lubricant accumulated in the recess flows downward through the main bearing 40, and a part of the lubricant is agitated by the hub portion and moves upward to reach the lower side of the end plate of the moving scroll and spreads over the thrust surface between the moving scroll and the main bearing housing as the moving scroll performs a translational rotation.

[0034] The working process and various functions of the compressor 1 are realized by driving the rotation of the rotor shaft 100 by the rotor of the motor. Specifically, the stator 20 of the motor is fixedly connected to the housing 10, and the rotor 200 is fixedly connected to the rotor shaft 100. When the motor is started, the rotor 200 rotates, thereby driving the rotation of the rotor shaft 100. Further, the rotor shaft 100 drives the compression mechanism to compress the working fluid, and at the same time, lubrication of each component is achieved through the lubrication mechanism as described above to ensure the normal operation of each component. During the operation of the compressor 1, the centrifugal force or centrifugal moment generated by the rotation of the eccentric component (such as the moving scroll) will cause vibration of the compressor. Therefore, generally, balance weights are provided on the rotating components (such as the rotor assembly) to provide a reverse centrifugal force or centrifugal moment to balance the unbalance generated by the eccentric component.

[0035] The following refers to Figures 1 to 4 , and specifically describes the rotating assembly according to the present invention. As Figure 2 shown, the rotating assembly 30 according to the first exemplary embodiment of the present invention may include a rotor 200, a balance weight 300, and a connecting member 400. The balance weight 300 and the rotor 200 may be fixed to each other through the connecting member 400 extending therethrough. The rotor shaft 100 may extend through the rotor 200 and the balance weight 300. The connecting member 400 may pass through all of the rotor 200 or only a part of the rotor 200. In an embodiment, the connecting member may be four or six.

[0036] During the operation of the compressor, the balance weight 300 rotates with the rotor 200, and thus centrifugal force will be generated. For the balance weight 300 with a large mass, a very large centrifugal force and bending moment will be generated during high-speed rotation, causing the balance weight 300 to tend to flip away from the rotor 200. Therefore, the connecting member 400 needs to overcome the shear force and bending moment to keep the balance weight 300 fixed to the rotor 200. During the working process of the compressor, the connecting member 400 is long-term subjected to such a very large acting force and bending moment, making it prone to fatigue wear, and causing the fixed connection between the balance weight 300 and the rotor 200 to become loose, and even causing the balance weight 300 to disengage from the rotor 200, thereby shortening the service life of the rotating assembly.

[0037] In a compressor, flat head rivets are usually used to fix the balance weight and the rotor. However, in this solution, on the one hand, the head of the rivet will bear a very large centrifugal force, and on the other hand, the rivet is prone to displacement in the socket, further increasing the bending moment acting on the head of the rivet, which makes the rivet very easy to fail.

[0038] In order to overcome the above problems, the inventors of the present application have proposed an improved rotating assembly. The following describes the inventors' idea in combination with specific embodiments.

[0039] Reference Figure 2 and Figure 3 , the balance weight 300 may include a first balance weight 310 (also referred to as an upper balance weight) disposed on the first side of the rotor 200 along the axial direction of the rotating assembly 30 (i.e., Figure 3 the upper side in Figure 3 ) and a second balance weight 320 (also referred to as a lower balance weight) disposed on the second side of the rotor 200 (i.e., Figure 3 the lower side in

[0040] Continuing to refer to Figure 2 and Figure 3 , the connecting member 400 may include a head 410 and a body 420 extending from the head along the axial direction of the rotating assembly. As Figure 2 and Figure 3 clearly shown, the head 410 may have a distal end away from the body 420 and a proximal end connected to the body 420, and the head 410 may taper in a direction from the distal end towards the proximal end. Preferably, as Figure 2 shown, the body 420 of the connecting member 400 may be formed in a cylindrical shape, and the head 410 of the connecting member may include a circular top surface 412 formed at the distal end and a tapered outer peripheral surface 414 between the circular top surface 412 and the cylindrical body 420. By adopting a connecting member with such a structure, the force on the head 410 of the connecting member can be made more uniform. However, the present disclosure is not limited thereto, and the connecting member 400 may also adopt other configurations. For example, the head may have a rectangular top surface and the body may be formed in a rectangle with a cross-sectional area smaller than the top surface, so that the head can taper from the rectangular top surface towards the body.

[0041] As Figure 3 clearly shown, an orifice 311 may be formed in the first balance weight 310, and the orifice 311 may include a first section 313 having a tapered aperture and a second section 315 having a uniform aperture, and the first section 313 may communicate with the second section 315.

[0042] In the assembled state of the rotating assembly 30, the head 410 of the connecting member 400 can be engaged in the first segment 313 of the orifice 311 and the body 420 of the connecting member can be inserted into the second segment 315 of the orifice of the first balance weight 310, the orifice of the rotor 200, and the orifice of the second balance weight 320. Preferably, the outer peripheral surface 414 of the head 410 can correspond to the shape of the first segment 313 of the orifice, that is to say, so that the outer peripheral surface 414 can abut against the orifice wall of the first segment as a whole without any gap, thereby providing an increased contact area and thus improving the fatigue strength of the connecting member 400. Of course, the outer peripheral surface 414 of the head 410 can be in contact with the first segment 313 only at a partial length. For example, the outer peripheral surface 414 can be in contact with the first segment only on its upper side and spaced apart from the first segment on its lower side.

[0043] As Figure 3 shown, the head 410 of the connecting member 400 contacts the first segment 313 of the balance weight along an inclined engagement surface. During the operation of the compressor, by changing the connecting member to have a tapered head, that is to say, in the present application, by changing the engagement mode of the head of the connecting member with the balance weight, the force application mode of the head is changed, and the bending moment acting on the head is also reduced, which can effectively improve the fatigue strength of the connecting member and the rotating assembly and extend the service life of the rotating assembly.

[0044] In addition, this tapered head 410 of the connecting member 400 can not only effectively reduce the bending moment caused by the centrifugal force, but also effectively reduce the action of the remaining non-axial forces. For example, when the compressor stops suddenly, the mass block will be subjected to a tangential force due to inertia. In this case, this tapered head of the connecting member can also play a role, thereby reducing the risk of the connecting member breaking.

[0045] In addition, in a conventional rotating assembly, only the body of the connecting member is fitted in the orifice. When the rotating assembly rotates under the action of centrifugal force, the body of the connecting member is prone to displacement in the orifice, which further increases the risk of stress concentration at the head of the connecting member and reduces the fatigue strength of the rotating assembly. In contrast, in the rotating assembly according to the exemplary embodiment of the present disclosure, the head of the connecting member can be fitted corresponding to the shape of the first segment of the orifice, and this fitting can prevent the connecting member from displacing in the orifice, thereby further improving the fatigue strength of the rotating assembly.

[0046] In a first exemplary embodiment according to the present application, the mass of the first balance weight 310 may be greater than the mass of the second balance weight 320. Accordingly, the first balance weight 310 will bear a greater centrifugal force. By providing an orifice including a tapered first section in the first balance weight 310 to receive the head 410 of the connecting member, the connecting member can be made to withstand such a large centrifugal force without suffering fatigue fracture. Of course, the present disclosure is not limited thereto, and other configurations of balance weights may also be provided. For example, the mass of the lower balance weight may be set to be greater than the mass of the upper balance weight, and an orifice 310 including a first section 313 may be provided in the second balance weight 320.

[0047] Alternatively, orifices 310 including a first section 313 may also be provided in both the first balance weight 310 and the second balance weight 320. In this case, the head 410 of the connecting member 400 may be respectively engaged in the orifices of the first balance weight 310 and the second balance weight 320. Exemplarily, the number of orifices 310 in the first balance weight 310 may be the same as the number of orifices in the second balance weight 320. Preferably, the same number of orifices 310 may be formed in the second counterweight portion 314 of the first balance weight 310 and the fourth counterweight portion 324 of the second balance weight. Since the second counterweight portion 314 and the fourth counterweight portion 324 are farther from the centroid of the balance weight, the bending moment generated by the centrifugal force is greater. By providing an orifice including a tapered first section in the second counterweight portion 314 and the fourth counterweight portion 324 to receive the head 410 of the connecting member, the connecting member can be made to withstand such a large centrifugal force without suffering fatigue fracture.

[0048] The connecting member 400 may be formed as a rivet, and fixed connection is achieved by flanging and riveting, for example by tapping, at the end of the body 420. Of course, the present disclosure is not limited thereto, and the connecting member may also be formed as other forms of connecting members such as screws.

[0049] Preferably, as Figure 3 shown, the inclination angle α of the outer peripheral surface 414 with respect to the horizontal direction (i.e., the lateral direction) is in the range of between 20 degrees and 60 degrees. The length of the head 410 in the axial direction may be in the range of 2 mm to 5 mm. In the case of the same inclination angle, the longer the length of the head, the greater the contact area between the head 410 and the balance weight. However, an excessively large length of the head may cause an increase in the size of the balance weight. Therefore, preferably, the length of the head is set in the range of 2 mm to 5 mm. In addition, the length of the body 420 in the axial direction may be in the range of 50 mm to 300 mm.

[0050] Continuing to refer to Figure 3, in the rotating assembly according to the present application, the head 410 of the connecting member 400 can be completely sunk into the orifice 311, that is to say, the head 410 of the connecting member 400 does not protrude relative to the first balance block 310 but is completely surrounded by the orifice 311 of the first balance block 310.

[0051] The inventors of the present application found through experimental comparison that compared with the existing rotating assemblies, the fatigue strength of the rotating assembly according to the present application can be increased by 15% relative to the fatigue strength of the conventional rotating assemblies. The above experimental results prove that the rotating assembly according to the present application can effectively maintain the fixed connection between the mass block and the rotating member, improve the fatigue strength of the rotating assembly, and extend the service life of the rotating assembly.

[0052] In addition, the rotating assembly according to the present application can withstand greater centrifugal force, so that larger balance blocks can be used in a compact structure as needed. And the rotating assembly according to the present application can be processed in a simple and easy way without complex modification of the existing rotating assembly, which is beneficial to realizing the improvement of the present invention on mass-produced die products (that is, it is beneficial to manufacture the rotating assembly according to the present invention on the basis of the existing die), shortening the project cycle and saving processing costs.

[0053] Although it is schematically described above that the rotating assembly according to the first exemplary embodiment of the present invention may include a rotating member formed as a rotor, balance blocks respectively disposed on both sides of the rotor as mass blocks, and a connecting member connecting the rotor and the balance blocks, those skilled in the art can understand that the present invention is not limited thereto, and the connecting member according to the present invention is equally applicable to other forms of rotating assemblies.

[0054] The following refers to Figure 4 to describe in detail the rotating assembly according to the second exemplary embodiment of the present application. The rotating assembly 30A according to the second exemplary embodiment of the present application may include: a balance block cover 500A, a mass block 300A, and a connecting member 400. The mass block 300A and the balance block cover 500A are only disposed on one side of the rotor 200A (that is, Figure 4 the upper side in ), and the mass block 300A and the balance block cover 500A are fixed to the rotor 200A so as to rotate as the rotor rotates. Here, the balance block cover 500A and the mass block 300A may respectively constitute the rotating member and the mass block of the rotating assembly 30A. The connecting member 400 may be substantially the same in structure and function as the above-mentioned connecting member 400. In the rotating assembly 30A according to the second exemplary embodiment of the present application, the connecting member 400 may extend through the mass block 300A to fix the mass block 300A to the balance block cover 400. Optionally, the connecting member 400 may further extend into the rotor 200A to fix the balance block cover 500A, the mass block 300A, and the rotor 200A together.

[0055] The rotating assembly 30A according to the second exemplary embodiment of the present invention can similarly effectively reduce the risk of breakage of the connecting member as the rotating assembly 30 according to the first exemplary embodiment of the present invention, and accordingly improve the fatigue strength of the rotating assembly and extend the service life of the rotating assembly.

[0056] This application allows various feasible variations. For example, although the rotating assembly for a compressor (particularly a scroll compressor) has been exemplarily described above, those skilled in the art should understand that the present invention is not limited thereto, and the rotating assembly according to the present invention can also be applied to various other rotary machines.

[0057] It should also be understood that the present invention is not limited to the specific embodiments described and illustrated in detail herein, and those skilled in the art can make various changes to the exemplary embodiments without departing from the scope defined by the claims. It should also be understood that, where the technical solutions are not contradictory, the features of each embodiment can be combined with each other or omitted.

Claims

1. A rotating assembly (30, 30A), comprising: a rotating member (200, 500A), a mass block (300, 300A), and a connecting member (400), the connecting member (400) extending through the mass block (300, 300A) to fix the mass block to the rotating member, characterized in that, the connecting member (400) includes a head (410) and a body (420) extending from the head in the axial direction of the connecting member (400), the head (410) having a distal end away from the body (420) and a proximal end connected to the body (420), and the head including a portion tapered in a direction from the distal end toward the proximal end.

2. The rotating assembly (30) according to claim 1, characterized in that, the rotating member is a rotor (200).

3. The rotating assembly (30) according to claim 2, characterized in that, the mass block is a balance block (300).

4. The rotating assembly (30) according to claim 1, characterized in that, the centroid of the mass block is offset from the rotation axis of the rotating assembly.

5. The rotating assembly (30) according to claim 1, characterized in that, the head (410) includes a top surface (412) formed at the distal end, and a tapered outer peripheral surface (414) exists between the top surface (412) and the body (420).

6. The rotating assembly according to claim 5, characterized in that, the inclination angle (α) of the tapered outer peripheral surface (414) with respect to the transverse direction of the connecting member (400) is in the range of 20 degrees to 60 degrees, and the transverse direction is perpendicular to the axial direction.

7. The rotating assembly according to claim 1, characterized in that, the length of the head (410) in the axial direction is in the range of 2 mm to 5 mm.

8. The rotating assembly according to claim 3, characterized in that, the balance block (300) includes a first balance block (310) provided on a first side of the rotor and a second balance block (320) provided on a second side of the rotor.

9. The rotating assembly according to claim 8, characterized in that, at least one of the first balance block (310) and the second balance block (320) is formed with an orifice (311), the orifice (311) including a first section (313) having a tapered aperture diameter and a second section (315) having a uniform aperture diameter, the first section communicating with the second section, and the outer peripheral surface (414) of the head corresponds to the shape of the first section (313) of the orifice.

10. The rotating assembly according to claim 9, characterized in that, the mass of the first balance block (310) is greater than the mass of the second balance block (320), and the orifice (311) is formed in the first balance block (310).

11. The rotating assembly according to claim 9, characterized in that, the head of the connecting member (410) is completely sunk into the orifice (311).

12. The rotating assembly according to any one of claims 1 to 11, wherein, the connecting member (400) is configured as a rivet.

13. A compressor, wherein, the compressor includes the rotating assembly (30, 30A) according to any one of claims 1 to 12.

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