Rotary drive assembly and rotary compressor

Abstract

The present application provides a rotary drive assembly for a rotary compressor, the rotary drive assembly comprising a rotor and a drive shaft rotated by the rotor, the rotary drive assembly further comprising a balance block assembly mounted at an axial end of the rotor, the balance block assembly comprising a balance block and a balance block cover, wherein at least a portion of the balance block cover is axially located between the rotor and the balance block. The present application also provides a rotary compressor. The rotary drive assembly and the rotary compressor according to the present application are not only simple in structure, but also easy to produce and install and low in cost.

Description

Technical Field

[0001] This invention relates to the field of rotary compressors, and more specifically, to a rotary drive assembly for a rotary compressor. Background Technology

[0002] This section provides background information related to the present invention, which does not necessarily constitute prior art.

[0003] Rotary compressors, such as scroll compressors, typically use a rotor to drive a drive shaft, which in turn drives an eccentric component to compress the working fluid. The centrifugal force or torque generated by the rotation of the eccentric component can cause problems such as compressor vibration and noise. A counterweight assembly is usually installed on the rotating component, such as the rotor, to provide a counter-centrifugal force or torque to balance the imbalance generated by the eccentric component. The counterweight assembly can be located above and / or below the rotor and includes a counterweight and a counterweight cover. The counterweight is fixedly connected to the rotor's aluminum column, while the counterweight cover is secured to the drive shaft by a fixing member, such as a retaining ring.

[0004] Therefore, the method of fixing the balance block cover is complex and costly. In addition, with the development of large-capacity scroll compressors, larger and heavier balance blocks are needed to adjust the dynamic balance of the compressor, which leads to problems such as insufficient connection strength between the balance block and the rotor aluminum ingot and easy failure. Summary of the Invention

[0005] This section provides a general overview of the invention, rather than a full disclosure of the invention's complete scope or all its features.

[0006] One of the objectives of this invention is to provide a rotary drive assembly for a rotary compressor, the rotary drive assembly including a rotor, a drive shaft and a balance block assembly, the balance block assembly including a balance block and a balance block cover, by setting the balance block cover between the rotor and the balance block in the axial direction, the balance block cover is fixedly installed without additional fixing components, making the production and installation of the rotary drive assembly simpler and cheaper.

[0007] Another object of the present invention is to provide a rotary drive assembly for a rotary compressor, the rotary drive assembly including a rotor, a drive shaft and a counterweight assembly, the counterweight assembly including a counterweight and a counterweight cover, wherein the counterweight portion of the counterweight protrudes axially toward the axial end of the rotor, which not only makes the press-fitting operation of the counterweight more convenient and the structure of the counterweight assembly more compact, but also helps the counterweight and the counterweight cover to form a generally cylindrical outer contour, thereby reducing the agitation of the surrounding fluid (e.g., oil) and avoiding the resulting reduction in efficiency.

[0008] Another object of the present invention is to provide a rotary drive assembly for a rotary compressor, the rotary drive assembly including a rotor, a drive shaft and a balance block assembly, the balance block assembly including a balance block and a balance block cover, particularly for the balance block assembly located below the rotor, the balance block (especially the lower balance block located below the rotor) is interference-fitted to the rotary shaft, which not only increases the fixed connection strength of the balance block and improves reliability, but also makes the press-fit operation more convenient, and is particularly suitable for large-horsepower scroll compressors.

[0009] Another object of the present invention is to provide a rotary compressor having the above-mentioned rotary drive assembly, which is not only simple in structure, easier to manufacture and install, but also low in cost and reliable in performance.

[0010] According to one aspect of the present invention, a rotary drive assembly for a rotary compressor is provided, the rotary drive assembly including a rotor and a drive shaft driven to rotate by the rotor, the rotary drive assembly further including a counterweight assembly mounted at an axial end of the rotor, the counterweight assembly including a counterweight and a counterweight cover, wherein at least a portion of the counterweight cover is axially located between the rotor and the counterweight.

[0011] Alternatively, the counterweight cover is fixed in place by at least a portion thereof being clamped axially between the rotor and the counterweight.

[0012] Optionally, the counterweight cover includes a fixing part and a housing part. The fixing part includes a first surface and an opposite second surface. The first surface of the fixing part contacts the axial end face of the rotor, the second surface of the fixing part contacts the counterweight, and the housing part protrudes axially from the second surface of the fixing part toward a direction away from the rotor.

[0013] Optionally, the balance block cover includes a recess that extends from the first surface of the fixed portion toward a direction away from the rotor.

[0014] Optionally, the counterweight includes a mounting portion and a counterweight portion, the counterweight portion protruding axially toward the rotor from a first surface of the mounting portion facing the rotor.

[0015] Optionally, the mounting portion includes a mounting hole for the drive shaft to pass through, and the mounting portion is interference-fitted with the drive shaft.

[0016] Alternatively, the balance weights and balance weight covers have complementary structures, resulting in a generally cylindrical outer profile for the balance weight assembly.

[0017] Optionally, the balance block includes a first arc-shaped section, a second arc-shaped section having a counterweight portion, and a cutting portion extending axially at the junction of the first and second arc-shaped sections of the balance block. The balance block cover includes a first arc-shaped section, a second arc-shaped section having a shell portion, and an axially extending fitting portion at the junction of the first and second arc-shaped sections of the balance block cover. The fitting portion is constructed in the form of a groove to accommodate the cutting portion.

[0018] Optionally, the balance block assembly is mounted below the rotor.

[0019] According to another aspect of the invention, a rotary compressor is provided, which includes a rotary drive assembly as described above.

[0020] Overall, the rotary drive assembly and rotary compressor according to the present invention bring at least one of the following beneficial effects: the balance block cover does not require additional fixing components for fixation, making it easy to manufacture and install, thereby reducing costs; the balance block and the balance block cover together form a generally cylindrical outer contour, reducing the agitation of the surrounding fluid and avoiding the impact on compressor efficiency; the press-fitting of the balance block is easier and the fixed connection is more reliable, making it particularly suitable for large-horsepower scroll compressors. Attached Figure Description

[0021] The features and advantages of one or more embodiments of the present invention will become more readily apparent from the following description with reference to the accompanying drawings. The drawings provided herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. The drawings are not drawn to scale and some features may be enlarged or reduced to show details of specific parts. In the drawings:

[0022] Figure 1 This is a longitudinal sectional view of a rotary compressor according to the present invention;

[0023] Figure 2 This is a longitudinal sectional view of the rotary drive assembly according to the present invention;

[0024] Figure 3 This is a three-dimensional schematic diagram of the balance block according to the present invention;

[0025] Figure 4 This is a three-dimensional schematic diagram of the balance block cover according to the present invention;

[0026] Figure 5 This is a three-dimensional schematic diagram of the balance block assembly according to the present invention;

[0027] Figure 6 This is a top view of the balance block assembly according to the present invention;

[0028] Figure 7It is a three-dimensional schematic diagram of the rotor and balance weight based on the comparative example; and

[0029] Figure 8 This is a longitudinal sectional view of the rotation drive component based on the comparative example. Detailed Implementation

[0030] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. This description is merely exemplary and does not constitute a limitation on the present invention and its applications.

[0031] First, refer to Figure 1 The general structure and operating principle of the rotary compressor according to the present invention are described herein. A scroll compressor is used as an example in the description, but it should be understood that the present invention is not limited to scroll compressors. Figure 1 As shown, the turbo compressor 100 includes a housing 10, a compression mechanism consisting of a fixed scroll member 20 and a moving scroll member 30, a drive shaft 60 for driving the compression mechanism, a motor 80, and main bearing housings 50 and secondary bearing housings 70 located at both ends of the drive shaft 60, respectively. The moving scroll member 30 includes an end plate 31, a hub 33 formed on one side of the end plate 31, and scroll blades 32 formed on the other side of the end plate 31. The fixed scroll member 20 includes an end plate 21 and scroll blades 22 formed on one side of the end plate 21. A series of compression chambers with volumes gradually decreasing from the radially outer to the radially inner side are formed between the scroll blades 22 of the fixed scroll member 20 and the scroll blades 32 of the moving scroll member 30 to compress the working fluid.

[0032] The compression of the working fluid within the compression chamber is achieved by the motor 80 driving the drive shaft 60 to rotate. Specifically, the motor 80 includes a stator 81 and a rotor 82. The stator 81 is fixedly connected to the housing 10, while the rotor 82 is fixedly connected to the drive shaft 60. When the motor 80 starts, the rotor 82 rotates, thereby driving the drive shaft 60 to rotate. One end of the drive shaft 60 (in...) Figure 1 The upper end of the drive shaft 60 (shown as the upper end) is supported by a main bearing housed in the main bearing housing 50. An eccentric crank pin 61 is provided at the upper end of the drive shaft 60, and an unloading bushing 62 is provided between the eccentric crank pin 61 and the hub 33 of the moving scroll component 30. The drive shaft 60 is rotated by the motor 80, thereby driving the moving scroll component 30. The moving scroll component 30 will rotate relative to the fixed scroll component 20 (i.e., the central axis of the moving scroll component 30 rotates about the central axis of the fixed scroll component 20, but the moving scroll component 30 itself does not rotate about its own central axis) to achieve fluid compression.

[0033] During operation of the scroll compressor 100, the centrifugal force or torque generated by the rotation of the eccentric component causes compressor vibration. Typically, a counterweight assembly is provided on the rotating component to provide a counter-centrifugal force or torque to balance the imbalance generated by the eccentric component. The shape, structure, and position of the counterweight assembly can vary according to specific application requirements. Figure 1 As shown, the balance block assembly may include an upper balance block assembly (including an upper balance block 42) disposed in the recess of the main bearing housing 50 above the rotor 82 and a lower balance block assembly (including a lower balance block 41 and a lower balance block cover 43) disposed below the rotor 82. However, those skilled in the art will understand that the compressor may also include only the upper balance block assembly or the lower balance block assembly, or include other balance block assemblies besides the upper and lower balance block assemblies.

[0034] The following description uses the balancing component as a preferred example to illustrate the rotary drive assembly according to the present invention. In this document, the rotary drive assembly according to the present invention is defined as an assembly consisting of a rotor, a drive shaft, and a balancing block assembly. Figure 2 As shown, the rotor 82 is generally cylindrical, and the drive shaft 60 passes through the central hole of the rotor 82 and is fixedly connected to the rotor 82. The lower balance block assembly is installed at one axial end (lower axial end) of the rotor 82 and is opposite to one axial end face (lower axial end face) of the rotor 82.

[0035] Figures 3 to 6 The specific structure of the lower balance block assembly is shown. The lower balance block assembly 41 includes a lower balance block 41 and a lower balance block cover 43. Figure 3 As shown, the lower balance block 41 includes a generally arc-shaped counterweight portion 412 and a generally annular mounting portion 411 for mounting the lower balance block 41 to the drive shaft 60. In other words, in the circumferential direction, the lower balance block 41 may include a first arc-shaped section 414 formed by a portion of the mounting portion 411 and a second arc-shaped section 416 formed by another portion of the mounting portion 411 and the counterweight portion 412. The radius of curvature of the second arc-shaped section 416 is larger than that of the first arc-shaped section 414. The mounting portion 411 includes a first surface 417 facing the rotor 82 and a second surface 418 opposite to the first surface 417. The counterweight portion 412 protrudes axially from the first surface 417 of the mounting portion 411 toward the rotor 82. A mounting hole 413 for the drive shaft 60 to pass through is also formed at the center of the mounting portion 411.

[0036] like Figure 4As shown, the lower counterweight cover 43 includes a generally arcuate outer shell portion 432 and a generally annular fixing portion 431 for fixing the lower counterweight cover 43 relative to the drive shaft 60. In other words, in the circumferential direction, the lower counterweight cover 43 may include a first arcuate section 434 formed by a portion of the fixing portion 431 and a second arcuate section 436 formed by another portion of the fixing portion 431 and the outer shell portion 432. The radius of curvature of the second arcuate section 436 is larger than that of the first arcuate section 434. The fixing portion 431 includes a first surface 437 facing the rotor 82 and a second surface 438 opposite to the first surface 437. The outer shell portion 432 protrudes from the second surface 438 of the fixing portion 431 in a direction away from the rotor 82. A through hole 433 for the drive shaft 60 to pass through is formed at the center of the fixing portion 431. The fixing part 431 also includes a recess 430 that is recessed from the first surface 437 of the fixing part 431 toward the direction away from the rotor 82, thereby reducing the overall weight of the lower balance block cover 43 to create an imbalance between it and the lower balance block 41.

[0037] Preferably, the lower balance block 41 and the lower balance block cover 43 are constructed with completely complementary outer contour shapes, such that when the lower balance block 41 and the lower balance block cover 43 are assembled together to form the lower balance block assembly, the lower balance block assembly has a generally cylindrical outer contour, thereby reducing the agitation of the surrounding fluid (e.g., oil in the oil sump at the bottom of the compressor) by the balance block assembly and avoiding the resulting increase in oil circulation rate and decrease in system efficiency. Specifically, as Figure 5 and Figure 6 As shown, the first arc-shaped section 414 of the lower balance block 41 and the first arc-shaped section 434 of the lower balance block cover 43 have approximately the same radius of curvature, and the second arc-shaped section 416 of the lower balance block 41 and the second arc-shaped section 436 of the lower balance block cover 43 have approximately the same radius of curvature. When the lower balance block 41 and the lower balance block cover 43 are assembled together, the mounting hole 413 of the lower balance block 41 is aligned with the through hole 433 of the lower balance block cover 43, the first surface 417 of the lower balance block 41 abuts against the second surface 438 of the lower balance block cover 43, the first arc-shaped section 414 of the lower balance block 41 is located below the first arc-shaped section 434 of the lower balance block cover 43 and almost completely overlaps with the first arc-shaped section 434 of the lower balance block cover 43, so that the outer shell portion 432 of the lower balance block cover 43 covers the radial outer surface of the first arc-shaped section 414 of the lower balance block 41, and the counterweight portion 412 of the lower balance block 41 covers the radial outer surface of the first arc-shaped section 434 of the lower balance block cover 43, so that the radial outer surface of the second arc-shaped section 416 of the lower balance block 41 and the radial outer surface of the lower balance block cover 43 together form the approximately cylindrical outer peripheral surface of the balance block assembly.

[0038] Preferably, the lower balance block 41 has a cutting portion 415 formed at the junction of its first arcuate section 414 and second arcuate section 416, extending axially from the second surface 418 of the mounting portion 411 to the top surface of the counterweight portion 412. The lower balance block cover 43 has an insert portion 435 formed at the junction of its first arcuate section 434 and second arcuate section 436, extending axially from the first surface 417 of the fixing portion 431 to the bottom surface of the outer shell portion 432. The insert portion 435 is constructed as an axially extending groove to accommodate the cutting portion 415 or even abut against it when the lower balance block 41 and the lower balance block cover 43 are assembled together. This makes the assembly between the lower balance block 41 and the lower balance block cover 43 more stable and facilitates a smooth transition at the junction of the radially outer surface of the lower balance block 41 and the radially outer surface of the lower balance block cover 43, thereby further reducing the impact of the lower balance block assembly on the surrounding fluid.

[0039] When the balance block assembly is installed onto the rotor 82 and drive shaft 60 to form a rotary drive assembly, see [link to relevant documentation]. Figure 2 The lower balance block 41 is fixed to the drive shaft 60. Preferably, the fixing part 431 of the lower balance block cover 43 is sandwiched between the lower balance block 41 (mounting part 411) and the rotor 82 (i.e., the first surface 437 of the fixing part 431 contacts the axial lower end face of the rotor 82, and the second surface 437 of the fixing part 431 contacts the first surface 417 of the mounting part 411 of the lower balance block 41), thereby fixing the lower balance block cover 43 relative to the drive shaft 60. Of course, those skilled in the art will understand that even if the fixing part 431 of the lower balance block cover 43 does not contact the rotor 82 and / or the lower balance block 41, the lower balance block cover 43 can still be substantially fixed relative to the drive shaft during the operation of the compressor because the fixing part 431 of the lower balance block cover 43 is located axially between the rotor 82 and the lower balance block 41, and because of the structural limitation between the lower balance block cover 43 and the lower balance block 41.

[0040] Preferably, the mounting portion 411 of the lower balance block 41 forms an interference fit with the drive shaft 60. Since the entire annular inner surface of the mounting hole 413 at the center of the mounting portion 411 can contact the drive shaft 60 and form an interference fit, the contact area is large, thus making the connection between the lower balance block 41 and the drive shaft 60 more stable.

[0041] The following will combine Figure 7 , Figure 8 The comparative examples shown illustrate the advantages and effects of the rotary drive assembly according to the present invention. See also Figure 8According to the comparative example, the rotary drive assembly consists of a rotor 82', a drive shaft 60, and a lower balance block assembly. The rotor 82' is generally cylindrical, and the drive shaft 60 passes through the central hole of the rotor 82' and is fixedly connected to the rotor 82'. The lower balance block assembly is mounted at one axial end (lower axial end) of the rotor 82' and is opposite to one axial end face (lower axial end face) of the rotor 82'.

[0042] Figure 7 A perspective view of the lower balance block and rotor assembled together is shown. An aluminum pillar 822' for mounting the lower balance block 41' is provided on the axial lower end face 821' of the rotor 82', that is, the aluminum pillar 822' extends axially downward from the axial lower end face 821' of the rotor 82'. The lower balance block 41' includes a generally arc-shaped counterweight portion 412' and a generally arc-shaped mounting portion 411' for mounting the lower balance block 41' to the rotor 82'. The mounting portion 411' includes a first surface 417' facing the rotor 82' and a second surface 418' opposite to the first surface 417'. The counterweight portion 412' protrudes axially from the second surface 418' of the mounting portion 411' in a direction away from the rotor 82', and the counterweight portion 412' is formed in the middle section of the mounting portion 411' in the circumferential direction. That is, as Figure 7 As shown, the mounting portion 411' of the lower balance block 41' includes two mounting ends protruding circumferentially from the counterweight portion 412', and each mounting end includes a mounting hole through which the aluminum column 822' passes. The lower balance block 41' is riveted or screwed onto the rotor 82' by inserting the aluminum column 822' into the respective mounting holes of the two mounting ends. However, for high-horsepower scroll compressors, larger and heavier lower balance blocks are usually required. The connection strength of the lower balance block to the aluminum column in the comparative example is insufficient, posing a risk of breakage and failure. Compared to this comparative example, in the rotary drive assembly according to the invention, the lower balance block 41 is fixed relative to the drive shaft 60 by an interference fit, resulting in greater connection strength and less susceptibility to breakage and failure, making it particularly suitable for high-horsepower scroll compressors. Furthermore, in the rotary drive assembly according to the present invention, since the counterweight portion 412 of the lower balance block 41 protrudes toward the rotor, and the second surface 418 of the lower balance block 41 is constructed as a flat and large-area press-fit surface, it makes the operation of press-fitting the lower balance block 41 onto the drive shaft 60 more convenient.

[0043] Additionally, see Figure 8In the rotary drive assembly according to the comparative example, the lower counterweight cover 43' includes a generally arc-shaped outer shell portion 432' and a generally annular fixing portion 431' for fixing the lower counterweight cover 43' relative to the drive shaft 60. The fixing portion 431' includes a first surface facing the rotor 82' and a second surface opposite to the first surface, and the outer shell portion 432' protrudes from the first surface of the fixing portion 431' toward the rotor 82'. A through hole for the drive shaft 60 to pass through is formed at the center of the fixing portion 431', and a retaining spring 45' is also provided on the second surface of the fixing portion 431' at the location of the through hole for fixing the lower counterweight cover 43' relative to the drive shaft 60. Compared with the comparative example, in the rotary drive assembly according to the invention, the lower counterweight cover 43 can be fixed relative to the drive shaft 60 without additional fixing members (such as retaining spring 45), resulting in a simpler structure, easier assembly, and lower cost.

[0044] Furthermore, after the lower balance block is assembled according to the comparative example, the first surface 417' of the mounting portion 411' of the lower balance block 41' contacts the axial lower end face 821' of the rotor 82', the second surface 418' of the mounting portion 411' of the lower balance block 41' faces the first surface of the fixing portion 431' of the lower balance block cover 43', and the top surface of the outer shell portion 432' of the lower balance block cover 43' can contact the axial lower end face 821' of the rotor 82' and substantially cover the portion of the axial lower end face 821' of the rotor 82' not covered by the first surface 417' of the mounting portion 411' of the lower balance block 41'. However, since the connection structure between the lower balance block 41' and the rotor aluminum column 822' is more complex, it is difficult to construct the lower balance block cover 43' into a structure that is completely complementary to the lower balance block 41', and it is also difficult to form a complete, approximately cylindrical outer contour together with the lower balance block 41'. Therefore, the lower balance block assembly may have a greater agitation effect on the surrounding fluid, thus producing adverse effects. Compared to the comparative example, in the rotary drive assembly according to the invention, the lower balance block 41 and the lower balance block cover 43 are constructed to have completely complementary outer contour shapes, such that the lower balance block assembly has a complete, generally cylindrical outer contour, thereby reducing the agitation of the surrounding fluid by the balance block assembly and avoiding, for example, an increase in oil circulation rate and a decrease in compressor system efficiency.

[0045] Additionally, it should be noted that although the rotary drive assembly preferably includes the lower balance block assembly in this document, those skilled in the art will understand that the upper balance block assembly can also adopt a similar structure and achieve the same effect in a rotary compressor.

[0046] Although various embodiments of the invention have been described in detail herein, it should be understood that the invention is not limited to the specific embodiments described and shown herein, and other modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention. All such modifications and variations fall within the scope of the invention. Moreover, all components described herein can be replaced by other technically equivalent components.

Claims

1. A rotary drive assembly for a rotary compressor (100), the rotary drive assembly comprising a rotor (82) and a drive shaft (60) driven to rotate by the rotor. The rotary drive assembly further includes a balance block assembly mounted at the axial end of the rotor, the balance block assembly comprising a balance block (41) and a balance block cover (43), characterized in that, At least a portion of the balance block cover is located axially between the rotor and the balance block, wherein the balance block includes a mounting portion (411) and a counterweight portion (412), the counterweight portion protruding axially toward the rotor from a first surface (417) of the mounting portion facing the rotor.

2. The rotary drive assembly for a rotary compressor (100) according to claim 1, wherein, The balance block cover is fixed in place by at least a portion of it being clamped axially between the rotor and the balance block.

3. The rotary drive assembly for a rotary compressor (100) according to claim 1, wherein, The balance block cover includes a fixing part (431) and an outer shell part (432). The fixing part includes a first surface (437) and an opposite second surface (438). The first surface (437) of the fixing part contacts the axial end face of the rotor, and the second surface (438) of the fixing part contacts the balance block (41). The outer shell part protrudes axially from the second surface (438) of the fixing part in a direction away from the rotor.

4. The rotary drive assembly for a rotary compressor (100) according to claim 3, wherein, The balance block cover includes a recess (430) that is recessed from the first surface (437) of the fixing part toward a direction away from the rotor.

5. The rotary drive assembly for a rotary compressor (100) according to claim 1, wherein, The mounting portion includes a mounting hole (413) through which the drive shaft passes, and the mounting portion is interference-fitted with the drive shaft.

6. The rotary drive assembly for a rotary compressor (100) according to any one of claims 1 to 4, wherein, The balance block and the balance block cover have complementary structures, so that the balance block assembly has a generally cylindrical outer contour.

7. The rotary drive assembly for a rotary compressor (100) according to any one of claims 1 to 4, wherein, The balance block includes a first arc-shaped section (414), a second arc-shaped section (416) having a counterweight (412), and a cutting portion (415) extending axially at the junction of the first arc-shaped section (414) and the second arc-shaped section (416) of the balance block. The balance block cover includes a first arc-shaped section (434), a second arc-shaped section (436) having an outer shell portion (432), and an axially extending insert portion (435) formed at the junction of the first arc-shaped section (434) and the second arc-shaped section (436) of the balance block cover. The insert (435) is constructed in the form of a groove to accommodate the cutting part (415).

8. The rotary drive assembly for a rotary compressor (100) according to any one of claims 1 to 4, wherein, The balance block assembly is mounted below the rotor.

9. A rotary compressor (100), characterized in that, The rotary compressor includes a rotary drive assembly according to any one of claims 1 to 8.

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