Compressor assembling method and compressor

Abstract

The invention relates to the technical field of vortex compressors, in particular to a compressor assembling method and a compressor. The compressor assembling method comprises the steps that (a) a shell, an upper bearing, a lower bearing, a bearing seat and a stator, a crankshaft and a rotor of a motor are provided; (b) fixedly mounting a stator and an upper bearing of the motor in the housing; (c) mounting the rotor on the crankshaft, wherein the outer diameter of the crankshaft corresponding to the rotor is D; (d) the crankshaft comprises a crankshaft upper bearing matching section and a crankshaft lower bearing matching section, and the outer diameter of the crankshaft lower bearing matching section is B; at least part of the upper bearing matching section of the crankshaft is placed below the upper bearing, or at least part of the upper bearing matching section of the crankshaft upwards extends out of the upper bearing; (e) fixedly connecting the bearing seat with the shell; (f) mounting the lower bearing on the bearing seat; and (g) installing the crankshaft upper bearing matching section into the upper bearing while installing the crankshaft lower bearing matching section into the lower bearing. Centering of the lower bearing is facilitated.

Description

Technical Field

[0001] This invention relates to the field of turbo compressor technology, and in particular to a compressor assembly method and a compressor. Background Technology

[0002] As a core component of refrigeration equipment, the compressor's performance and reliability have a decisive impact on the equipment's efficiency and stability. The compressor's performance and reliability largely depend on the precision of its assembly. Currently, commonly used scroll compressors have a motor, which includes a stator, a crankshaft, and a rotor fixed to the crankshaft. The crankshaft is supported by two bearings, an upper bearing and a lower bearing, allowing it to rotate around its axis of rotation.

[0003] During compressor assembly, the upper and lower bearings need to be concentrically positioned. Typically, the upper bearing and stator are fixed first, and then the lower bearing, crankshaft, and rotor are installed. Since the upper bearing is already fixed, the concentric positioning of the upper and lower bearings can only be achieved by adjusting the lower bearing.

[0004] However, in this situation, the stator is fixed, the rotor is fixed to the crankshaft, and the lower bearing is fitted onto the crankshaft. Centering the lower bearing requires overcoming the magnetic force between the stator and rotor, and it's crucial to avoid damaging the crankshaft during this process. Therefore, a significant force is needed to achieve concentric adjustment of these two bearings. This creates positioning difficulties, potentially leading to low centering accuracy, or even making centering impossible, or requiring the investment of expensive centering equipment. Summary of the Invention

[0005] To overcome at least one of the aforementioned defects and problems in the prior art, the present invention provides a compressor assembly method.

[0006] According to a specific embodiment of the present invention, a compressor assembly method is provided, comprising the steps of:

[0007] (a): Provide housing, upper bearing, lower bearing, bearing housing, and stator, crankshaft and rotor of the motor; (b): The stator and the upper bearing of the motor are fixedly installed inside the housing; (c): The rotor is mounted on the crankshaft, and the outer diameter of the crankshaft at the location corresponding to the rotor is D; (d): The crankshaft includes an upper bearing mating section and a lower bearing mating section, wherein the outer diameter of the lower bearing mating section is B; At least a portion of the bearing mating section on the crankshaft is placed below the upper bearing, or at least a portion of the bearing mating section on the crankshaft extends upward beyond the upper bearing; (e): The bearing housing is fixedly connected to the housing; (f): Install the lower bearing on the bearing housing; (g): The upper crankshaft bearing mating section is installed into the upper bearing, and the lower crankshaft bearing mating section is installed into the lower bearing.

[0008] In a preferred embodiment, in step (d), placing at least a portion of the crankshaft upper bearing mating section below the upper bearing is equivalent to placing the crankshaft upper bearing mating section below the upper bearing.

[0009] In a preferred embodiment, in step (d), when at least a portion of the crankshaft upper bearing mating section is placed below the upper bearing, or when the crankshaft upper bearing mating section is placed below the upper bearing, the crankshaft further includes a crankshaft mating portion with an outer diameter of C. The lower bearing includes a lower bearing inner bore with a lower bearing inner bore surface and an inner diameter of A. At this time, the crankshaft mating portion is aligned horizontally with the location where the lower bearing is to be installed, and the outer diameter C is smaller than the inner diameter A, so that a first gap is left between the crankshaft mating portion and the inner bore surface of the lower bearing (assuming it has already been installed). In a preferred embodiment, A, B, and C satisfy: BC < B K (0 < K < 0.5).

[0010] In a preferred embodiment, D, B, and A satisfy the following condition: D > A > B > C.

[0011] In a preferred embodiment, after the upper bearing section of the crankshaft is installed into the upper bearing in step (g), there is an air gap E between the inner diameter of the stator and the outer diameter of the rotor.

[0012] In a preferred embodiment, A, C, and E satisfy: AC ≥ 2 E.

[0013] In a preferred embodiment, the crankshaft mating portion is provided with a first chamfer.

[0014] In a preferred embodiment, the first chamfer and the extension line of the crankshaft lower bearing mating section have an included angle α, wherein α satisfies 0° < α < 60°.

[0015] In a preferred embodiment, while the upper crankshaft bearing mating section is installed into the upper bearing in step (g), the lower crankshaft bearing mating section is installed into the lower bearing by means of the first chamfer mating with the inner bore surface of the lower bearing.

[0016] In a preferred embodiment, in step (d), extending at least a portion of the crankshaft upper bearing mating section upwards from the upper bearing constitutes placing the crankshaft upper bearing mating section above the upper bearing.

[0017] In a preferred embodiment, in step (d), when at least a portion of the crankshaft upper bearing mating section extends upward beyond the upper bearing or when the crankshaft upper bearing mating section is placed above the upper bearing, a second gap is left in the vertical direction between the lower end face of the crankshaft lower bearing mating section and the upper end face of the assumed installed lower bearing. The lower bearing includes a lower bearing inner hole, and the lower bearing inner hole has a lower bearing inner hole surface.

[0018] In a preferred embodiment, a second chamfer is provided on the lower crankshaft bearing mating section.

[0019] In a preferred embodiment, while the upper crankshaft bearing mating section is installed into the upper bearing in step (g), the lower crankshaft bearing mating section is installed into the lower bearing by means of the second chamfer mating with the inner bore surface of the lower bearing.

[0020] To overcome at least one aspect of the aforementioned defects and problems in the prior art, the present invention provides a compressor comprising: shell; An upper bearing is fixedly installed inside the housing; An electric motor, housed within the housing, the electric motor comprising: The stator is fixedly installed inside the housing; The crankshaft includes an upper crankshaft bearing mating section, a lower crankshaft bearing mating section, and a crankshaft mating part. The outer diameter of the lower crankshaft bearing mating section is B, and the outer diameter of the crankshaft mating part is C. The upper crankshaft bearing mating section is supported by the upper bearing. The outer diameter C of the crankshaft mating part is smaller than the outer diameter B of the lower crankshaft bearing mating section. The rotor is fixed on the crankshaft and can rotate relative to the stator, and the outer diameter of the crankshaft corresponding to the rotor is D; The bearing housing is fixedly connected to the outer casing; The lower bearing is connected to the bearing housing and supports the crankshaft lower bearing mating section. The lower bearing includes a lower bearing inner hole with an inner diameter of A.

[0021] In a preferred embodiment, B and C satisfy the condition: B > C.

[0022] In a preferred embodiment, A, B, and C satisfy: BC < B K (0 < K < 0.5).

[0023] In a preferred embodiment, D and B satisfy the condition: D > A > B.

[0024] In a preferred embodiment, an air gap E exists between the inner diameter of the stator and the outer diameter of the rotor.

[0025] In a preferred embodiment, A, C, and E satisfy: AC ≥ 2 E.

[0026] In a preferred embodiment, the crankshaft mating portion is provided with a first chamfer.

[0027] In summary, through the technical solution of this invention, the crankshaft mating part is machined into a narrow neck. During compressor assembly, the crankshaft bearing mating section with the rotor installed is first placed below the upper bearing, aligning the narrow neck portion (crankshaft mating part) horizontally with the area where the lower bearing is to be installed. A first gap is left between the outer diameter of the narrow neck portion (crankshaft mating part) and the inner diameter of the assumed installed lower bearing inner hole. This first gap ensures that when the magnetic rotor is in close contact with the stator, the narrow neck portion (crankshaft mating part) will not touch the inner surface of the lower bearing under the magnetic force between the stator and rotor. This method ensures that the lower bearing will not come into contact with the narrow neck of the crankshaft (crankshaft mating part) during centering, facilitating the centering of the lower bearing (making the lower bearing concentric with the upper bearing). After the lower bearing is centered and installed, the crankshaft and rotor assembly is pressed into the final position. In addition, the crankshaft mating part has a first chamfer. When the crankshaft and rotor assembly is pressed into the final position, the crankshaft lower bearing mating section is installed into the lower bearing by means of the first chamfer and the mating with the inner hole surface of the lower bearing. This ensures that the inner hole surface of the lower bearing will not be damaged during the pressing process. This method is easy to operate and can achieve the assembly of fixed-frequency compressors and variable-frequency compressors on a single production line with low cost. Alternatively, during compressor assembly, the crankshaft upper bearing mating section with the rotor mounted on it can be placed above the upper bearing, leaving a second vertical gap between the lower end face of the crankshaft lower bearing mating section and the upper end face of the assumed installed lower bearing. This second gap ensures that the lower bearing will not touch the crankshaft during centering and installation. On the one hand, the crankshaft will not affect the centering (concentricity) and installation of the lower bearing; on the other hand, the lower bearing will not damage the crankshaft. Furthermore, the crankshaft lower bearing mating section has a second chamfer. When the crankshaft and rotor are pressed into their final position, the crankshaft lower bearing mating section, with the help of the second chamfer, fits into the inner bore of the lower bearing, ensuring that the inner bore of the lower bearing will not be damaged during the pressing process. This method is convenient to operate and requires low-cost investment to enable the assembly of fixed-frequency compressors and variable-frequency compressors to share a single production line. Attached Figure Description

[0028] Figure 1This is a side view of the crankshaft in Embodiment 1 of this application; Figure 2 This is an enlarged view of section J in Embodiment 1 of this application; Figure 3 This is a perspective view of the crankshaft in Embodiment 1 of this application; Figure 4 This is a schematic diagram of the rotor mounted on the crankshaft in Embodiment 1 of this application; Figure 5 This is a schematic diagram of the installation step one of Embodiment 1 of this application, in which the bearing housing and the lower bearing are not installed; Figure 6 This is a schematic diagram assuming that the bearing housing and the lower bearing have been installed in step one of the installation steps of Embodiment 1 of this application; Figure 7 for Figure 5 Enlarged view at point F; Figure 8 This is a schematic diagram of the second installation step in Embodiment 1 of this application; Figure 9 This is a schematic diagram of installation step three in Embodiment 1 of this application; Figure 10 For Figure 8 Enlarged view at point G; Figure 11 This is an intermediate process diagram of pressing the crankshaft and rotor assembly into the final position in step four of the installation step of Embodiment 1 of this application; Figure 12 This is a schematic diagram of the crankshaft and rotor assembly being pressed into the final position in step four of the installation process of Embodiment 1 of this application. Figure 13 This is an assembly diagram of the bearing housing and lower bearing in step three of the installation process in Embodiment 1 of this application; Figure 14 This is an exploded view of the assembly of the bearing housing and lower bearing in step three of the installation process in Embodiment 1 of this application; Figure 15 This is a side view of the crankshaft in Embodiment 2 of this application; Figure 16 This is a perspective view of the crankshaft in Embodiment 2 of this application; Figure 17 This is a schematic diagram of the rotor mounted on the crankshaft in Embodiment 2 of this application; Figure 18 This is a schematic diagram of the installation step one of Embodiment 2 of this application, in which the bearing housing and lower bearing are not installed; Figure 19 This is a schematic diagram assuming that the bearing housing and the lower bearing have been installed in step one of the installation steps in Embodiment 2 of this application; Figure 20 for Figure 18 Enlarged view at point H; Figure 21This is a schematic diagram of the second installation step in Embodiment 2 of this application; Figure 22 This is a schematic diagram of installation step three in Embodiment 2 of this application; Figure 23 For Figure 21 Enlarged view at point I; Figure 24 This is an intermediate process diagram of pressing the crankshaft and rotor assembly into the final position in step four of the installation process of Embodiment 2 of this application; Figure 25 This is a schematic diagram of the crankshaft and rotor assembly being pressed into the final position in step four of the installation process of Embodiment 2 of this application. Figure 26 This is an assembly diagram of the bearing housing and lower bearing in step three of the installation process in Embodiment 2 of this application; Figure 27 This is an exploded view of the assembly of the bearing housing and the lower bearing in step three of the installation process in Embodiment 2 of this application.

[0029] Explanation of reference numerals in the attached drawings: 100, compressor; 1, housing; 21, stator; 22, crankshaft; 221, upper crankshaft bearing mating section; 222, lower crankshaft bearing mating section; 223, crankshaft mating part; 224, first chamfer; 225, second chamfer; 23, rotor; 3, upper bearing; 31, upper bearing bushing; 4, bearing housing; 5, lower bearing; 51, lower bearing inner bore surface; 52, first clearance; 53, second clearance; A, inner diameter of the lower bearing inner bore; B, outer diameter of the crankshaft lower bearing mating section; C, outer diameter of the crankshaft mating part; D, crankshaft outer diameter corresponding to the rotor; E, air gap between the stator inner diameter and the rotor outer diameter. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] As attached Figure 1 -Appendix Figure 14 As shown, Embodiment 1 of the present invention discloses a compressor assembly method, comprising the following steps: (a): Provide housing 1, upper bearing 3, bearing housing 4, lower bearing 5, lower bearing retaining ring (not shown in the figure), as well as stator 21, crankshaft 22 and rotor 23 of motor; (b): The stator 21 and the upper bearing 3 of the motor are fixedly installed inside the housing 1; (c): Refer to Appendix Figure 3The rotor 23 is mounted on the crankshaft 22, and the outer diameter of the crankshaft at the point corresponding to the rotor 23 is D; (d): Installation step one, refer to the appendix Figure 1 and appendix Figure 5 -Appendix Figure 7 The crankshaft 22 includes an upper crankshaft bearing mating section 221, a lower crankshaft bearing mating section 222, and a crankshaft mating part 223. The outer diameter of the lower crankshaft bearing mating section 222 is B, and the outer diameter of the crankshaft mating part 223 is C. B and C satisfy B > C. The crankshaft mating part 223 is provided with a first chamfer 224. The lower bearing 5 includes a lower bearing inner hole with a lower bearing inner hole surface 51. The inner diameter of the lower bearing inner hole is A. D, A, and B satisfy D > A > B (because the lower crankshaft bearing mating section 222 needs to be installed in the lower bearing inner hole, A must be greater than B; when the rotor 23 is installed on the crankshaft 22, the lower crankshaft bearing mating section 222 needs to pass through the inside of the rotor 23, so D must be greater than B). A, B, and C satisfy BC < B. K (0 < K < 0.5), place the crankshaft upper bearing mating section 221 below the upper bearing 3. At this time, the crankshaft mating part 223 is aligned with the position where the lower bearing 5 is to be installed in the horizontal direction (i.e., the heights of the two are matched). The outer diameter C of the crankshaft mating part 223 is smaller than the inner diameter A of the lower bearing inner hole, so that a first gap is left between the crankshaft mating part 223 and the assumed lower bearing inner hole surface 51 that has been installed. At this time, the crankshaft 22 will not be displaced under the action of the magnetic force between the stator 21 and the rotor 23. (e): Installation step two, refer to the appendix Figure 8 The bearing housing 4 is fixedly connected to the inner wall of the outer casing 1; (f): Installation step three, refer to the appendix Figure 9 Appendix Figure 10 Appendix Figure 13 Appendix Figure 14The lower bearing 5 is installed on the bearing housing 4. When installing the lower bearing 5, the first gap 52 ensures that when the magnetic rotor 23 is in close contact with the stator 21, the crankshaft neck (crankshaft mating part 223) will not touch the inner surface 51 of the lower bearing under the magnetic force between the stator 21 and the rotor 23 (because B > C). This ensures that the lower bearing 5 will not touch the crankshaft neck (crankshaft mating part 223) when it is centered, making it easier to center the lower bearing 5. The specific method of installing the lower bearing 5 is as follows: the upper bearing 3 is used as a reference to position the lower bearing retaining ring and the positioned lower bearing retaining ring is fixedly connected to the bearing housing 4. The lower bearing 5 is then positioned using the lower bearing retaining ring as a reference. The inner side of the lower bearing retaining ring... With a chamfer, the outer side of the lower bearing 5 is positioned by engaging with the chamfer to enter the inner side of the lower bearing retaining ring, so that the upper bearing 6 and the lower bearing 5 are concentric. The positioned lower bearing 5 is then fixedly connected to the bearing housing 4. By setting the lower bearing retaining ring, during centering, the lower bearing 5 is not included, only the lower bearing retaining ring, which is not affected by magnetic force, is centered. After centering the lower bearing retaining ring and the upper bearing 3, the lower bearing retaining ring is fastened to the bearing housing 4. Then the lower bearing 5 is pressed into the lower bearing retaining ring. At this time, the lower bearing 5 is concentric with the upper bearing 3, which facilitates the centering and installation of the lower bearing 5. By setting a chamfer at the contact position between the lower bearing 5 and the lower bearing retaining ring, it is easy to press the lower bearing 5 into the lower bearing retaining ring. (g): Installation step four, refer to the appendix Figure 11 -Appendix Figure 12 After the lower bearing 5 is centered and installed, the crankshaft 22 and rotor 23 are pressed into their final position (that is, the upper bearing mating section 221 of the crankshaft is installed into the upper bearing 3, and the lower bearing mating section 222 of the crankshaft is installed into the lower bearing 5). Furthermore, the crankshaft mating section 223 has a first chamfer 224, and there is an angle α between the first chamfer 224 and the extension line of the lower bearing mating section 222 of the crankshaft, where α satisfies 0° < α < 60°. When the crankshaft 22 and rotor 23 are pressed into their final position, the upper bearing mating section 221 of the crankshaft is installed into the upper bearing 3, and the lower bearing mating section 222 of the crankshaft is installed into the lower bearing 5 by means of the first chamfer 224 mating with the inner bore surface 51 of the lower bearing. This ensures that the inner bore surface 51 of the lower bearing will not be damaged during the pressing process. After the crankshaft 22 and rotor 23 are pressed into their final position, there is an air gap E between the inner diameter of the stator 21 and the outer diameter of the rotor 23, where A, C, and E satisfy AC ≥ 2. E (AC is the radial gap value of the centering process in this embodiment 1 when the rotor 23 is tightly attached to the inner wall of the stator 21. This value must be greater than or equal to twice the air gap E in order to ensure the realization of the centering process).

[0032] As attached Figure 15 -Appendix Figure 27 As shown, Embodiment 2 of the present invention discloses a compressor assembly method, including the following steps: (a): Provide housing 1, upper bearing 3, bearing housing 4, lower bearing 5, lower bearing retaining ring (not shown in the figure), as well as stator 21, crankshaft 22 and rotor 23 of motor; (b): The stator 21 and the upper bearing 3 of the motor are fixedly installed inside the housing 1; (c): Refer to Appendix Figure 16 The rotor 23 is mounted on the crankshaft 22; (d): Installation step one, refer to the appendix Figure 18 -Appendix Figure 20 The crankshaft 22 includes an upper bearing mating section 221 and a lower bearing mating section 222. The lower bearing 5 includes a lower bearing inner hole with a lower bearing inner hole surface 51. The upper bearing mating section 221 is placed above the upper bearing 3. At this time, the lower end face of the lower bearing mating section 222 and the upper end face of the assumed installed lower bearing 5 have a second gap 53 in the vertical direction. At this time, the crankshaft 22 will not be displaced under the action of the magnetic force between the stator 21 and the rotor 23. (e): Installation step two, refer to the appendix Figure 21 The bearing housing 4 is fixedly connected to the inner wall of the outer casing 1; (f): Installation step three, refer to the appendix Figure 22 Appendix Figure 23 Appendix Figure 26 Appendix Figure 27 The lower bearing 5 is installed on the bearing housing 4. During installation, the second clearance 53 ensures that the lower bearing 5 will not touch the crankshaft 22 during centering and installation. This prevents the crankshaft 22 from affecting the centering and installation of the lower bearing 5, and also prevents damage to the lower bearing 5. The specific method for installing the lower bearing 5 is as follows: using the upper bearing 3 as a reference, the lower bearing retaining ring is positioned and fixedly connected to the bearing housing 4. The lower bearing 5 is then positioned using the lower bearing retaining ring as a reference. The inner side of the lower bearing retaining ring has a chamfer, and the outer side of the lower bearing 5 enters the lower bearing housing 4 through the chamfer. The inner side of the bearing retaining ring is used to position the lower bearing 5 so that the upper bearing and the lower bearing 5 are concentric. The positioned lower bearing 5 is fixedly connected to the bearing housing 4. By setting the lower bearing retaining ring, during centering, the lower bearing 5 is not included, and only the lower bearing retaining ring, which is not affected by magnetic force, is centered. After centering the lower bearing retaining ring and the upper bearing 3, the lower bearing retaining ring is fastened to the bearing housing 4. Then the lower bearing 5 is pressed into the lower bearing retaining ring. At this time, the lower bearing 5 is concentric with the upper bearing 3, which facilitates the centering and installation of the lower bearing 5. By setting a chamfer at the contact position between the lower bearing 5 and the lower bearing retaining ring, it is easy to press the lower bearing 5 into the lower bearing retaining ring. (g): Installation step four, refer to the appendix Figure 24 -Appendix Figure 25After the lower bearing 5 is centered and installed, the crankshaft 22 and rotor 23 are pressed into their final position (that is, the upper bearing mating section 221 of the crankshaft is installed into the upper bearing 3, while the lower bearing mating section 222 of the crankshaft is installed into the lower bearing 5). In addition, the lower bearing mating section 222 of the crankshaft is provided with a second chamfer 225. When the crankshaft 22 and rotor 23 are pressed into their final position, the upper bearing mating section 221 of the crankshaft is installed into the upper bearing 3, while the lower bearing mating section 222 of the crankshaft is installed into the lower bearing 5 by means of the second chamfer 225 and the mating with the inner hole surface 51 of the lower bearing. This can ensure that the inner hole surface 51 of the lower bearing will not be damaged during the pressing process.

[0033] As attached Figure 1 -Appendix Figure 14 As shown, Embodiment 3 of the present invention discloses a compressor 100, including: a housing 1, a motor, an upper bearing 3, a bearing seat 4, a lower bearing 5, and a lower bearing retaining ring (not shown in the figure).

[0034] The motor is housed in the housing 1. The motor includes: stator 21, crankshaft 22, rotor 23, and upper bearing 3 including upper bearing bushing 31. The stator 21 and upper bearing 3 are fixedly installed in the housing 1. The rotor 23 is fixed on the crankshaft 22 and can rotate relative to the stator 21. The outer diameter of the crankshaft corresponding to the rotor 23 is D. There is an air gap E between the inner diameter of the stator 21 and the outer diameter of the rotor 23.

[0035] The crankshaft 22 includes an upper bearing mating section 221, a lower bearing mating section 222, and a crankshaft mating part 223. The outer diameter of the lower bearing mating section 222 is B. The upper bearing mating section 221 is supported by the upper bearing sleeve 31 of the upper bearing 3. The outer diameter of the crankshaft mating part 223 is C. The outer diameter of the crankshaft mating part 223 is smaller than the outer diameter of the lower bearing mating section 222, i.e., B and C satisfy B > C. The crankshaft mating part 223 is provided with a first chamfer 224. The outer diameter of the first chamfer 224 gradually increases from top to bottom. The lowest point of the first chamfer 224 (at...) Figure 1 The outer diameter of the upper bearing section 221 (located at its leftmost end) is consistent with the outer diameter of the lower bearing mating section 222 of the crankshaft. The first chamfer 224 and the extension line of the lower bearing mating section 222 of the crankshaft have an included angle α, where α satisfies 0° < α < 60°. The upper bearing mating section 221 and the lower bearing mating section 222 of the crankshaft refer to the sections where the crankshaft 22 mates with the upper bearing 3 and the lower bearing mating section 222 respectively, after the crankshaft 22, rotor 23, upper bearing 3, and lower bearing 4 are fully installed.

[0036] The bearing housing 4 is fixedly connected to the housing 1. The bearing housing 4 is located on the side of the housing 1 near the bottom and is fixedly connected to the inner wall of the housing 1. The bearing housing 4 may have a shaft hole or an opening to allow the crankshaft 22 to pass through the bearing housing 4.

[0037] The lower bearing retaining ring is fixedly connected to the bearing housing 4.

[0038] The lower bearing 5 includes a lower bearing inner hole, which has an inner hole surface 51. The inner diameter of the lower bearing inner hole is A. D, A, and B satisfy the condition: D > A > B. A, B, and C satisfy the condition: BC < B. K (0 < K < 0.5), A, C, and E satisfy AC ≥ 2 E, the lower bearing 5 is connected to the bearing housing 4 and installed inside the lower bearing retaining ring, and the lower bearing 5 supports the crankshaft lower bearing mating section 222.

[0039] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A compressor assembling method, comprising the steps of: (a) providing a housing, an upper bearing, a lower bearing, a bearing seat, and a stator, a crankshaft and a rotor of a motor; (b) fixedly mounting the stator and the upper bearing of the motor in the housing; (c) mounting the rotor on the crankshaft, the outer diameter of the crankshaft at the position corresponding to the rotor being D; (d) the crankshaft comprising a crankshaft upper bearing fitting section and a crankshaft lower bearing fitting section, the outer diameter of the crankshaft lower bearing fitting section being B; at least part of the crankshaft upper bearing fitting section being placed below the upper bearing, or at least part of the crankshaft upper bearing fitting section extending upwardly beyond the upper bearing; (e) fixedly connecting the bearing seat with the housing; (f) mounting the lower bearing on the bearing seat; (g) mounting the crankshaft upper bearing fitting section into the upper bearing while the crankshaft lower bearing fitting section is mounted into the lower bearing.

2. The compressor assembling method according to claim 1, wherein: in step (d), the at least part of the crankshaft upper bearing fitting section being placed below the upper bearing is that the crankshaft upper bearing fitting section is placed below the upper bearing.

3. The compressor assembling method according to any one of claims 1 to 2, wherein: in step (d), when the at least part of the crankshaft upper bearing fitting section is placed below the upper bearing or the crankshaft upper bearing fitting section is placed below the upper bearing, the crankshaft further comprises a crankshaft fitting portion, the outer diameter of the crankshaft fitting portion being C, the lower bearing comprises a lower bearing inner hole, the lower bearing inner hole having a lower bearing inner hole surface, the inner diameter of the lower bearing inner hole being A, at this time, the crankshaft fitting portion is aligned with the position where the lower bearing is to be mounted in the horizontal direction, the outer diameter C is smaller than the inner diameter A, so that a first gap is left between the crankshaft fitting portion and the lower bearing inner hole surface which is assumed to have been mounted.

4. The compressor assembling method according to claim 3, wherein: the first gap is left between the crankshaft fitting portion and the lower bearing inner hole surface which is assumed to have been mounted.

5. The compressor assembling method according to claim 3, wherein: the D, the B, the A and the C satisfy the condition of D>A>B>C.

6. The compressor assembling method according to claim 3, wherein: in step (g), after the crankshaft upper bearing fitting section is mounted into the upper bearing, there is a gap E between the inner diameter of the stator and the outer diameter of the rotor.

7. The compressor assembling method according to claim 6, wherein: the gap E is left between the inner diameter of the stator and the outer diameter of the rotor.

8. The compressor assembling method according to claim 3, wherein: the crankshaft fitting portion is provided with a first chamfer.

9. The compressor assembling method according to claim 8, wherein: the first chamfer and the extension line of the crankshaft lower bearing fitting section form an included angle a, the a satisfying the condition of 0°<a<60°.

10. The compressor assembling method according to any one of claims 8 or 9, wherein: the first chamfer is provided with a second chamfer. ​ ​ ​ ​ The A, the B and the C satisfy: B-C < B K (0 < K < 0.5). ​ ​ ​ ​ ​ The A and the C and the E satisfy: A-C≥2 E. ​ ​ ​ ​ ​ In step (g), the upper bearing fitting section of the crankshaft is fitted into the upper bearing, and the lower bearing fitting section of the crankshaft is fitted into the lower bearing by cooperation of the first chamfer and the inner hole surface of the lower bearing.

11. The compressor assembling method according to claim 1, wherein: In step (d), at least part of the upper bearing fitting section of the crankshaft is extended upward beyond the upper bearing or the upper bearing fitting section of the crankshaft is placed above the upper bearing.

12. The compressor assembling method according to any one of claims 1 or 11, wherein: In step (d), at least part of the upper bearing fitting section of the crankshaft is extended upward beyond the upper bearing or the upper bearing fitting section of the crankshaft is placed above the upper bearing, and the lower end surface of the lower bearing fitting section of the crankshaft and the upper end surface of the lower bearing, which is assumed to be fitted, leave a second gap in the vertical direction.

13. The compressor assembling method according to claim 12, wherein: A second chamfer is provided on the lower bearing fitting section of the crankshaft.

14. The compressor assembling method according to claim 13, wherein: In step (g), the upper bearing fitting section of the crankshaft is fitted into the upper bearing, and the lower bearing fitting section of the crankshaft is fitted into the lower bearing by cooperation of the second chamfer and the inner hole surface of the lower bearing.

15. A compressor, comprising: a housing; an upper bearing fixedly installed in the housing; a motor accommodated in the housing, the motor comprising: a stator fixedly installed in the housing; a crankshaft comprising an upper bearing fitting section, a lower bearing fitting section, and a fitting portion, the outer diameter of the lower bearing fitting section being B, the outer diameter of the fitting portion being C, the upper bearing fitting section being supported by the upper bearing, the outer diameter C of the fitting portion being smaller than the outer diameter B of the lower bearing fitting section; a rotor fixed to the crankshaft and capable of rotating relative to the stator, the outer diameter of the crankshaft corresponding to the rotor being D; a bearing seat fixedly connected to the housing; a lower bearing connected to the bearing seat and supporting the lower bearing fitting section of the crankshaft, the lower bearing comprising a lower bearing inner hole, the inner diameter of the lower bearing inner hole being A.

16. The compressor according to claim 15, wherein: B and C satisfy B > C.

17. The compressor according to claim 15, wherein: The A, the B and the C satisfy: B-C < B K (0 < K < 0.5).

18. The compressor according to claim 15, wherein: D, A, and B satisfy D > A > B.

19. The compressor of claim 15, wherein: There is an air gap E between the inner diameter of the stator and the outer diameter of the rotor.

20. The compressor according to claim 19, wherein: The A and the C and the E satisfy: A-C≥2 E.

21. The compressor of claim 15, wherein: The fitting portion is provided with a first chamfer.

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