Rotary compressor and refrigeration equipment

Abstract

The utility model discloses a rotary compressor and refrigeration equipment, the rotary compressor comprises a pump body assembly, a motor assembly, a crankshaft and a bearing assembly, and the pump body assembly comprises an air cylinder; the motor assembly comprises a stator and a rotor; the crankshaft is connected with the rotor and the cylinder; the bearing assembly comprises a bearing body and a first flexible structure, the bearing body is provided with a shaft hole and a through hole, the shaft hole and the through hole are arranged in the axial direction and communicate with each other, the bearing body is located on the side, away from the pump body assembly, of the motor assembly and sleeves the end of the crankshaft through the shaft hole, and the first flexible structure is located at the end, close to the through hole, of the shaft hole and surrounds the crankshaft. The outer wall of the first flexible structure and the inner wall of the through hole are arranged in a spaced mode and define an annular groove, the outer wall of the first flexible structure is an inclined face, and the thickness of the first flexible structure in the radial direction of the bearing body is gradually increased in the direction from a groove opening of the annular groove to the groove bottom of the annular groove. According to the rotary compressor, the lubricity between the crankshaft and the bearing assembly is good, abrasion can be reduced, and the reliability is high.

Description

Technical Field

[0001] This utility model relates to the field of compressor technology, and in particular to a rotary compressor and refrigeration equipment. Background Technology

[0002] With the increasing speed and efficiency of rotary compressors, and the use of high-density motors in specific environments, ensuring the coaxiality of the motor stator and rotor during operation, as well as reducing crankshaft end deformation, has become particularly important for guaranteeing the reliability of rotary compressors. To achieve this, some rotary compressors use motor bearings installed at the motor ends. However, when conventional sliding bearings are used as motor bearings, the bearings themselves are prone to wear, resulting in relatively poor reliability and affecting the overall reliability of the rotary compressor. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a rotary compressor with good lubrication between its crankshaft and bearing assembly, which reduces wear and increases reliability.

[0004] This utility model also provides a refrigeration device having the above-mentioned rotary compressor.

[0005] A rotary compressor according to a first aspect of the present invention includes a pump body assembly including a cylinder; a motor assembly including a stator and a rotor, the stator being arranged around the rotor; a crankshaft passing through and connected to the rotor, the crankshaft including an eccentric portion rotatably disposed within the cylinder; and a bearing assembly including a bearing body and a first flexible structure, the bearing body having a shaft hole and a through hole, the shaft hole and the through hole being arranged axially and communicating, the inner diameter of the through hole being larger than the inner diameter of the shaft hole, the bearing body being located on the side of the motor assembly away from the pump body assembly and sleeved on the end of the crankshaft through the shaft hole, the first flexible structure being located at the end of the shaft hole near the through hole and arranged around the crankshaft, the outer wall of the first flexible structure being spaced apart from the inner wall of the through hole and defining an annular groove, the outer wall of the first flexible structure being an inclined surface, and the thickness of the first flexible structure increasing radially from the opening of the annular groove to the bottom of the annular groove.

[0006] The rotary compressor according to the first aspect of this utility model has at least the following beneficial effects: By setting the first flexible structure and the annular groove, the structural stiffness of the first flexible structure is reduced, making it easier for the first flexible structure to deform under external force. During the operation of the rotary compressor, when the crankshaft comes into contact with the inner wall of the bearing assembly, the first flexible structure deforms along with the end of the crankshaft, thereby increasing the contact area between the crankshaft and the inner wall, reducing the surface pressure, increasing the minimum oil film thickness, and thus improving the lubrication between the crankshaft and the bearing assembly, reducing wear. At the same time, because the thickness of the first flexible structure increases gradually, the structural stiffness of the first flexible structure changes gradually, and there is no sudden change in structural stiffness, especially at the root of the first flexible structure. Therefore, it can avoid the disadvantage of the force being concentrated at the root of the first flexible structure and the large force at the root causing fracture, and it can also avoid excessive surface pressure at the root, so that the crankshaft and the bearing assembly maintain a good lubrication state, effectively extending the service life of the bearing assembly and improving its reliability, and improving the overall reliability of the rotary compressor.

[0007] According to some embodiments of the present invention, the first flexible structure and the bearing body are integrally formed.

[0008] According to some embodiments of the present invention, the first flexible structure includes a head and a root, the root being connected to the bearing body, the head extending axially toward the bearing body and radially toward the bearing body, and the minimum thickness at the end face of the head being T1, satisfying: 1mm≤T1≤4mm.

[0009] According to some embodiments of the present invention, along the radial direction of the bearing body, the maximum thickness of the first flexible structure at the root is T2, and along the axial direction of the bearing body, the height of the first flexible structure is h1, satisfying: 0.09≤(T2-T1) / h1≤1, where T1<T2.

[0010] According to some embodiments of this utility model, the inner diameter of the shaft hole is D, and the height of the first flexible structure along the axial direction of the bearing body is h1, satisfying: h1≤0.5D.

[0011] According to some embodiments of the present invention, along the axial direction of the bearing body, the height of the first flexible structure is h1, and the sum of the height of the first flexible structure and the height of the shaft hole is H, satisfying: h1 / H≤2 / 3.

[0012] According to some embodiments of the present invention, along the axial direction of the bearing body, the height of the first flexible structure is h1, which satisfies: 1.5mm≤h1≤20mm.

[0013] According to some embodiments of the present invention, along the radial direction of the bearing body, the width of the annular groove at the bottom of the groove is B, which satisfies: B≥1mm.

[0014] According to some embodiments of the present invention, the bearing assembly further includes a bushing, the bushing being disposed in the shaft hole and partially extending into the through hole, the bearing body having a second flexible structure, the second flexible structure being located at one end of the shaft hole near the through hole and arranged around the bushing, the portion of the bushing extending into the through hole and the second flexible structure forming the first flexible structure.

[0015] According to some embodiments of the present invention, the bushing includes a friction-reducing coating, which is attached to the inner peripheral wall of the bushing.

[0016] The refrigeration equipment according to a second aspect of the present invention includes the rotary compressor of the first aspect of the present invention.

[0017] The refrigeration equipment according to the second aspect of this utility model has at least the following beneficial effects: Because the refrigeration equipment uses the aforementioned rotary compressor, the structural stiffness of the first flexible structure is reduced by setting a first flexible structure and an annular groove, making the first flexible structure prone to deformation under external force. During the operation of the rotary compressor, when the crankshaft contacts the inner wall of the bearing assembly, the first flexible structure deforms along with the end of the crankshaft, thereby increasing the contact area between the crankshaft and the inner wall, reducing surface pressure, increasing the minimum oil film thickness, and thus improving the lubrication between the crankshaft and the bearing assembly, reducing wear. Simultaneously, because the thickness of the first flexible structure increases gradually, the structural stiffness of the first flexible structure changes gradually, without abrupt changes in structural stiffness, especially at the root of the first flexible structure. Therefore, it avoids the disadvantage of concentrated force at the root of the first flexible structure and the large force at the root causing breakage, and it also avoids excessive surface pressure at the root, maintaining good lubrication between the crankshaft and the bearing assembly, effectively extending the service life of the bearing assembly and improving reliability, and improving the overall reliability of the rotary compressor.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0020] Figure 1 This is a cross-sectional schematic diagram of the internal structure of the rotary compressor in an embodiment of this utility model;

[0021] Figure 2 yes Figure 1 Cross-sectional view of the bearing assembly;

[0022] Figure 3 This is a cross-sectional view of the bearing assembly in another embodiment of the present invention;

[0023] Figure 4 This is a graph showing how the minimum oil film thickness varies with the minimum wall thickness T1 of the first flexible structure in this embodiment of the present invention.

[0024] Figure 5 This is a graph showing the change of surface pressure at the root of the first flexible structure in this embodiment of the invention as a function of the ratio (T2-T1) / h1;

[0025] Figure 6 This is a graph showing how the deformation ratio of the crankshaft changes with the ratio h1 / H in this embodiment of the present invention.

[0026] Figure 7 This is a graph showing how the minimum oil film thickness varies with the height h1 of the first flexible structure in this embodiment of the invention.

[0027] Figure label:

[0028] Pump body assembly 100; first cylinder 110; first compression chamber 111; first roller 112; second cylinder 120; second compression chamber 121; second roller 122; first bearing 130; second bearing 140; partition plate 150;

[0029] Motor assembly 200; stator 210; rotor 220; counterweight 221;

[0030] Crankshaft 300; Eccentric part 310;

[0031] Bearing assembly 400; bearing body 410; main body 411; mounting part 412; through hole 413; first flexible structure 420; head 421; root 422; shaft hole 430; annular groove 440; bushing 450; second flexible structure 460. Detailed Implementation

[0032] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0033] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0034] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0035] In the description of this utility model, unless otherwise explicitly defined, terms such as setting, installing, connecting, assembling, and cooperating should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0036] With the increasing speed and efficiency of rotary compressors, and the use of high-density motors in specific environments, ensuring the coaxiality of the motor stator and rotor during operation, as well as reducing crankshaft end deformation, has become particularly important for ensuring the reliability of rotary compressors. To this end, some rotary compressors achieve these goals by installing motor bearings at the motor ends.

[0037] However, when using conventional sliding bearings as motor bearings, two problems arise. First, the motor bearings themselves are prone to wear, resulting in relatively poor reliability. Second, because the crankshaft is connected to the motor rotor, during the operation of the rotary compressor, the motor stator generates a magnetic attraction force on the rotor, causing a slight radial offset. Simultaneously, to balance the centrifugal force of the crankshaft's eccentric portion, balance weights are installed at both ends of the rotor, located at the radial ends. During operation, these balance weights also cause a slight radial offset of the rotor. All of these factors lead to bending deformation at the crankshaft end, meaning the crankshaft end tilts relative to the rotor's axis of rotation. At this point, the contact between the crankshaft end and the motor bearing becomes point contact, where the oil film thickness is the minimum required. Point contact results in a small minimum oil film thickness, leading to abnormal wear on both the crankshaft and motor bearings. This ultimately affects the overall reliability of the rotary compressor.

[0038] Therefore, referring to Figures 1 to 3As shown, the first aspect of this utility model provides a rotary compressor, which can be a single-cylinder rotary compressor or a double-cylinder rotary compressor.

[0039] Reference Figure 1 The diagram shown is a cross-sectional view of the internal structure of a rotary compressor, omitting the housing. It can be understood that the rotary compressor includes a pump body assembly 100, a motor assembly 200, a crankshaft 300, and a bearing assembly 400. The pump body assembly 100 is a dual-cylinder structure. Specifically, the pump body assembly 100 includes a first cylinder 110 and a second cylinder 120. The pump body assembly 100 also includes a first bearing 130, a second bearing 140, and a partition 150. The first cylinder 110 is positioned above the second cylinder 120, and the partition 150 is sandwiched between the first cylinder 110 and the second cylinder 120. The first bearing 130 is positioned above the first cylinder 110, and the second bearing 140 is positioned below the second cylinder 120. In other words, the first cylinder 110 and the second cylinder 120 are located between the first bearing 130 and the second bearing 140. The first cylinder 110 is provided with a first compression chamber 111 and a first roller 112 installed in the first compression chamber 111. Similarly, the second cylinder 120 is provided with a second compression chamber 121 and a second roller 122 installed in the second compression chamber 121. The lower part of the crankshaft 300 passes through the first bearing 130, the first cylinder 110, the partition 150, the second cylinder 120, and the second bearing 140 in sequence. The lower part of the crankshaft 300 is provided with two eccentric parts 310. The eccentric directions of the two eccentric parts 310 are different. The two eccentric parts 310 are rotatably disposed in the first compression chamber 111 and the second compression chamber 121, respectively, thereby realizing the connection between the crankshaft 300 and the first cylinder 110 and the crankshaft 300 and the second cylinder 120.

[0040] Reference Figure 1 As shown, it can be understood that by setting the first bearing 130 and the second bearing 140, the bearings are supported and positioned to bear the reaction force of the compressed gas in the first cylinder 110 and the second cylinder 120 during the operation of the rotary compressor, thereby improving the working stability of the first cylinder 110 and the second cylinder 120.

[0041] Reference Figure 1As shown, the motor assembly 200 is connected to the crankshaft 300 and located above the pump body assembly 100. Specifically, the motor assembly 200 includes a stator 210 and a rotor 220. Typically, the stator 210 is fixedly connected to the housing of the rotary compressor and is annular. The rotor 220 is disposed within the inner ring of the stator 210, i.e., the stator 210 is arranged around the rotor 220, and the rotor 220 is fixedly connected to the crankshaft 300, i.e., the crankshaft 300 passes through the rotor 220. The rotor 220 can rotate relative to the stator 210. Under the action of a magnetic field, the rotor 220 can be driven to rotate relative to the stator 210. Thus, the rotor 220 drives the eccentric portion 310 to rotate through the crankshaft 300, thereby compressing the refrigerant in the first compression chamber 111 and the second compression chamber 121.

[0042] Reference Figure 1 As shown, it can be understood that, in order to balance the centrifugal force of the eccentric portion 310 of the crankshaft 300, balance blocks 221 are installed at both the upper and lower ends of the rotor 220, and the two balance blocks 221 at the upper and lower ends are located at both ends of the rotor 220 in the radial direction, that is, the two balance blocks 221 are arranged on opposite sides. Therefore, the balance of the rotor 220 during rotation can be improved, the radial offset of the rotor 220 can be reduced, the coaxiality of the stator 210 and the rotor 220 can be improved, and the dynamic and static balance effect can be improved.

[0043] Reference Figure 1 and Figure 2 As shown, it can be understood that, in order to improve the coaxiality of the stator 210 and rotor 220, prevent the stator 210 and rotor 220 from rubbing against each other, and reduce the deflection deformation at the end of the crankshaft 300, a bearing assembly 400 is also installed at the upper end of the crankshaft 300, that is, the bearing assembly 400 is located on the side of the rotor 220 away from the pump body assembly 100. Specifically, the bearing assembly 400 includes a bearing body 410, which includes a main body portion 411 and a mounting portion 412. The main body portion 411 is cylindrical, and the mounting portion 412 is connected to the upper end of the main body portion 411 and is annular. The mounting portion 412 is arranged around the main body portion 411, and the bearing body 410 can be fixedly installed through the mounting portion 412. The main body portion 411 and the mounting portion 412 are integrally formed structures, which are easy to manufacture.

[0044] Reference Figure 2 As shown, the main body 411 is provided with a shaft hole 430 and a through hole 413. The shaft hole 430 and the through hole 413 are arranged and connected along the axial direction of the crankshaft 300 (i.e., the axial direction of the bearing body 410), wherein the through hole 413 is located on the upper side of the shaft hole 430. Generally, the central axis of the through hole 413 coincides with that of the shaft hole 430, and the inner diameter of the through hole 413 is larger than that of the shaft hole 430, thus forming a stepped hole between the through hole 413 and the shaft hole 430.

[0045] Reference Figure 1 and Figure 2 As shown, it can be understood that the upper end of the crankshaft 300 passes through the shaft hole 430, that is, the bearing body 410 is sleeved on the upper end of the crankshaft 300 through the shaft hole 430, thereby positioning the upper end of the crankshaft 300 through the bearing body 410, so as to improve the coaxiality between the stator 210 and the rotor 220 and reduce the bending deformation of the end of the crankshaft 300.

[0046] Reference Figure 2 As shown, the first flexible structure 420 is an annular wall structure. The first flexible structure 420 is located at the end of the shaft hole 430 opposite to the motor assembly 200, i.e., at the upper end of the shaft hole 430, and is located within the through hole 413. The first flexible structure 420 is arranged around the crankshaft 300, and the space surrounded by the first flexible structure 420 is not part of the shaft hole 430. The side of the first flexible structure 420 facing the central axis of the through hole 413 is defined as the inner peripheral wall, and the side facing away from the central axis of the through hole 413 is defined as the outer peripheral wall. The outer peripheral wall of the first flexible structure 420 is spaced apart from the inner peripheral wall of the through hole 413, defining an annular groove 440. It is easy to understand that the annular groove 440 is arranged around the first flexible structure 420. Thanks to the annular groove 440, the first flexible structure 420 is suspended on both sides of the crankshaft 300 in the radial direction, that is, the first flexible structure 420 is similar to a cantilever structure, which reduces the structural stiffness at the first flexible structure 420. Under the action of external force, the first flexible structure 420 is prone to deformation in the radial direction of the crankshaft 300.

[0047] Reference Figure 2 As shown, it can be understood that the first flexible structure 420 is connected to the bearing body 410 and is an integrally formed structure. That is to say, the first flexible structure 420 can be directly processed or formed on the bearing body 410. For example, the integral structure composed of the first flexible structure 420 and the bearing body 410 can be directly cast by mold, or the first flexible structure 420 can be obtained by cutting on the bearing body 410, which is convenient for production.

[0048] Reference Figure 2As shown, it can be understood that the lower end of the first flexible structure 420 is connected to the end face between the shaft hole 430 and the through hole 413, and the upper end of the first flexible structure 420 extends upward, that is, the upper end of the first flexible structure 420 extends along the axial direction of the bearing body 410. The upper end of the first flexible structure 420 is defined as the head 421, and the lower end of the first flexible structure 420 is defined as the root 422. The side of the first flexible structure 420 facing the annular groove 440 is an inclined surface, that is, the outer peripheral wall of the first flexible structure 420 is an inclined surface, which is inclined relative to the central axis of the crankshaft 300. The inner peripheral wall of the first flexible structure 420 is parallel to the central axis of the crankshaft 300, and the inner peripheral wall of the first flexible structure 420 is coplanar with the inner wall of the shaft hole 430, forming the inner wall of the bearing body 410. From the head 421 towards the root 422, that is, from the opening of the annular groove 440 towards the bottom of the annular groove 440 or from top to bottom, the thickness (i.e., wall thickness) of the first flexible structure 420 increases radially along the bearing body 410. In other words, the wall of the first flexible structure 420 has a structure that is smaller at the top and larger at the bottom. Therefore, the structural stiffness of the first flexible structure 420 increases from the head 421 towards the root 422; that is, the structural stiffness of the first flexible structure 420 is variable axially along the bearing body 410.

[0049] Therefore, by setting the first flexible structure 420 and the annular groove 440, the structural stiffness of the first flexible structure 420 is reduced, making the first flexible structure 420 more prone to deformation. Furthermore, the thickness of the first flexible structure 420 increases from top to bottom, resulting in a gradual change in its structural stiffness. During the operation of the rotary compressor, when the end of the crankshaft 300 undergoes flexural deformation, the crankshaft 300 comes into contact with the inner wall of the bearing body 410, with the contact area mainly being the upper and lower sides of the shaft hole 430. On the one hand, under the force of the crankshaft 300, the first flexible structure 420 deforms along with the end deformation of the crankshaft 300, so that the contact between the crankshaft 300 and the inner wall of the bearing body 410 changes from point contact to surface contact, that is, the crankshaft 300 is in surface contact at the first flexible structure 420, thereby increasing the contact area between the crankshaft 300 and the inner wall of the bearing body 410, reducing the surface pressure, which is the load borne per unit area, thereby increasing the oil film thickness at the contact point, that is, increasing the minimum oil film thickness, thereby improving the lubrication between the crankshaft 300 and the bearing body 410 and reducing wear.

[0050] On the other hand, when the crankshaft 300 contacts the first flexible structure 420, since the structural stiffness of the first flexible structure 420 is gradually changing, the crankshaft 300 and the head 421 of the first flexible structure 420 begin to contact, that is, the first flexible structure 420 begins to deform from the head 421. Subsequently, the contact area between the crankshaft 300 and the first flexible structure 420 gradually expands towards the root 422, so that the contact area between the crankshaft 300 and the first flexible structure 420 gradually increases, and the stiffness of the first flexible structure 420 also gradually increases. This is beneficial to maintaining the stability of the oil film between the crankshaft 300 and the bearing body 410, and further increasing the minimum oil film thickness. Meanwhile, the first flexible structure 420 does not have abrupt changes in structural stiffness, especially at the root 422. Therefore, it can avoid the disadvantage of force concentration at the root 422 of the first flexible structure 420 and the large force at the root 422 causing fracture. It can also avoid excessive surface pressure at the root 422, so that the crankshaft 300 and the bearing body 410 maintain a good lubrication state, effectively extending the service life of the bearing assembly 400 and improving its reliability, thereby improving the overall reliability of the rotary compressor.

[0051] Referring to Table 1, it is easy to understand that under the same operating conditions: Example 1: Without the first flexible structure 420 and the annular groove 440, the minimum oil film thickness is 2.36 μm; Example 2: With the first flexible structure 420 and the annular groove 440, and with the wall thickness of the first flexible structure 420 being uniform, the minimum oil film thickness is 3.0 μm, which is greater than the minimum oil film thickness in Example 1; Example 3: With the first flexible structure 420 and the annular groove 440, and with the wall thickness of the first flexible structure 420 increasing from the head 421 to the root 422, the minimum oil film thickness is 3.42 μm, which is greater than the minimum oil film thickness in Example 2. Therefore, the first flexible structure 420, whose structural stiffness increases from the head 421 to the root 422, can further increase the minimum oil film thickness.

[0052] Table 1: Comparison of minimum oil film thickness under different schemes

[0053]

[0054] Referring to Table 2, it is easy to understand that under the same working conditions, in Example 4, the wall thickness of the first flexible structure 420 is uniform, and the surface pressure at the root 422 is 30 MPa; in Example 5, the wall thickness of the first flexible structure 420 increases from the head 421 to the root 422, and the surface pressure at the root 422 is 22 MPa. Therefore, the first flexible structure 420, whose structural stiffness increases from the head 421 to the root 422, can reduce the surface pressure at the root 422, thereby avoiding the disadvantage of force concentration at the root 422 causing fracture, extending service life, and improving reliability.

[0055] Table 2: Comparison of surface pressure at the root of the first flexible structure under different schemes

[0056] Example plan The surface pressure (MPa) at the root of the first flexible structure Four The first flexible structure has a uniform wall thickness. 30 five The wall thickness of the first flexible structure increases from the head to the root. 22

[0057] In other embodiments, it is understood that when the through hole 413 is located below the shaft hole 430, the first flexible structure 420 is located at the end of the shaft hole 430 facing the motor assembly 200. Similarly, the first flexible structure 420 can increase the contact area between the crankshaft 300 and the inner wall of the bearing body 410, improving lubrication, which will not be elaborated here.

[0058] Reference Figure 2 As shown, it can be understood that the minimum thickness (i.e., wall thickness) at the end face of the head 421 along the radial direction of the bearing body 410 is defined as T1. That is, the minimum wall thickness of the first flexible structure 420 is T1. This satisfies: 1mm ≤ T1 ≤ 4mm. It is easy to understand that when the minimum wall thickness of the first flexible structure 420 is too small, the structural stiffness of the first flexible structure 420 decreases, and the first flexible structure 420 itself is prone to deformation, resulting in a decrease in the supporting force on the crankshaft 300, causing increased deformation of the crankshaft 300, and making it difficult to maintain the stability of the oil film thickness, i.e., the oil film thickness will deteriorate. When the minimum wall thickness of the first flexible structure 420 is too large, the flexibility of the first flexible structure 420 is insufficient, and it cannot increase the contact area between the crankshaft 300 and the inner wall of the bearing body 410, resulting in a minimum oil film thickness that is too small, deteriorating the oil film thickness, intensifying wear, and even causing abnormal wear.

[0059] Reference Figure 4 As shown, it is easy to understand that under the same operating conditions, as the minimum wall thickness T1 of the first flexible structure 420 increases, the minimum oil film thickness first increases and then decreases. When 1mm ≤ T1 ≤ 4mm is satisfied, the minimum oil film thickness is greater than or equal to 1.5μm; when T1 < 1mm or T1 > 4mm, the minimum oil film thickness is less than 1.5μm. Therefore, by ensuring that 1mm ≤ T1 ≤ 4mm, for example, T1 = 1mm, T1 = 2mm, T1 = 3mm, or T1 = 4mm, the structural stiffness of the first flexible structure 420 is kept within a suitable range, so that the minimum oil film thickness is sufficiently large to improve lubricity.

[0060] Reference Figure 2As shown, it can be understood that, along the radial direction of the bearing body 410, the maximum thickness (i.e., wall thickness) of the first flexible structure 420 at the root 422 is defined as T2. In other words, the maximum wall thickness of the first flexible structure 420 is T2, and it is easy to understand that T2 > T1. Along the axial direction of the bearing body 410, the height of the first flexible structure 420 is defined as h1, satisfying: 0.09 ≤ (T2 - T1) / h1 ≤ 1. (T2 - T1) / h1 is the ratio of the maximum wall thickness difference of the first flexible structure 420 to its height, which represents the shape parameter of the first flexible structure 420. When the value of (T2-T1) / h1 is too small, the wall thickness of the first flexible structure 420 tends to be uniform, and the structural stiffness of the first flexible structure 420 from the head 421 to the root 422 is basically equal. However, if the structural stiffness of the first flexible structure 420 is too small, the first flexible structure 420 itself is prone to deformation. The first flexible structure 420 provides insufficient support to the crankshaft 300, affecting the coaxiality between the stator 210 and the rotor 220. This can easily cause the stator 210 and the rotor 220 to rub against each other, leading to increased deformation of the crankshaft 300. Furthermore, it can cause the force exerted by the crankshaft 300 on the bearing body 410 to be concentrated at the root 422 of the first flexible structure 420, resulting in excessive surface pressure at the root 422 of the first flexible structure 420. This reduces the oil film thickness, which is deteriorating the oil film thickness and is not conducive to the formation of the oil film. Consequently, the wear at the root 422 is aggravated. When the value of (T2-T1) / h1 is too large, the wall thickness at the root 422 of the first flexible structure 420 will increase, resulting in excessive stiffness and small deformation at the root 422. This will also cause the force exerted by the crankshaft 300 on the bearing body 410 to be concentrated at the root 422 of the first flexible structure 420, resulting in excessive surface pressure at the root 422 of the first flexible structure 420, a smaller oil film thickness, i.e., deterioration of the oil film thickness, which is not conducive to the formation of the oil film and exacerbates the wear at the root 422.

[0061] Reference Figure 5 As shown, it is easy to understand that under the same working conditions, as the ratio (T2-T1) / h1 increases, the surface pressure at the root 422 of the first flexible structure 420 first decreases and then increases. When 0.09≤(T2-T1) / h1≤1 is satisfied, the surface pressure at the root 422 of the first flexible structure 420 is relatively small, such as remaining below approximately 26MPa. When (T2-T1) / h1<0.09 or (T2-T1) / h1>1, the surface pressure at the root 422 of the first flexible structure 420 is relatively large, such as above approximately 26MPa. Therefore, by setting 0.09≤(T2-T1) / h1≤1, for example, (T2-T1) / h1=0.2, (T2-T1) / h1=0.4 or (T2-T1) / h1=0.8, the surface pressure of the first flexible structure 420 at the root 422 can be reduced, which is conducive to the formation of oil film and increases the oil film thickness, improves lubricity, reduces the wear of the first flexible structure 420 at the root 422, and thus improves the reliability of the bearing assembly 400.

[0062] Reference Figure 2 As shown, it can be understood that the inner diameter of the shaft hole 430 along the radial direction of the bearing body 410 is D, satisfying: h1≤0.5D. That is, the height of the first flexible structure 420 is less than or equal to half the inner diameter of the shaft hole 430. With a fixed inner diameter of the shaft hole 430, when the height of the first flexible structure 420 is greater than half the radial direction of the shaft hole 430, the flexibility of the first flexible structure 420 increases, the structural stiffness decreases significantly, the first flexible structure 420 itself is prone to deformation, the supporting force on the crankshaft 300 decreases, resulting in increased deformation of the crankshaft 300, and is detrimental to maintaining the stability of the oil film thickness, i.e., the oil film thickness deteriorates. Therefore, ensuring h1≤0.5D, while meeting the flexibility requirements, guarantees that the first flexible structure 420 has an effective supporting function, maintaining the stability of the oil film thickness, increasing the minimum oil film thickness, improving lubrication, reducing wear, and thus improving the reliability of the bearing assembly 400 and the rotary compressor.

[0063] Reference Figure 2 As shown, it can be understood that along the axial direction of the bearing body 410, the sum of the height of the first flexible structure 420 and the height of the shaft hole 430 is defined as H, that is, the distance from the upper end of the first flexible structure 420 to the lower end of the bearing body 410 is H, satisfying: h1 / H≤2 / 3. Generally, the sum of the height of the first flexible structure 420 and the height of the shaft hole 430 is constant. When the height of the first flexible structure 420 is too large, that is, the height of the shaft hole 430 decreases, the height of the through hole 413 increases, and the depth of the annular groove 440 increases, on the one hand, the structural stiffness of the first flexible structure 420 decreases, the first flexible structure 420 itself is prone to deformation, the support force on the crankshaft 300 decreases, causing the crankshaft 300 to deform more, and it is not conducive to maintaining the stability of the oil film thickness, that is, the oil film thickness will deteriorate. On the other hand, the decrease in the height of the shaft hole 430 will lead to insufficient support of the bearing body 410 on the crankshaft 300 at the shaft hole 430, resulting in insufficient support of the bearing body 410 on the crankshaft 300 as a whole, affecting the coaxiality between the stator 210 and the rotor 220, and easily causing the stator 210 and the rotor 220 to rub against each other. At the same time, it will lead to increased deformation of the crankshaft 300.

[0064] Reference Figure 6 As shown, it is easy to understand that under the same operating conditions, the deformation of crankshaft 300 increases with the increase of the ratio h1 / H.

[0065] Therefore, by making h1 / H≤2 / 3, under the condition that the first flexible structure 420 meets the flexibility requirements, it can be ensured that the first flexible structure 420 has an effective supporting role, so as to maintain the stability of the oil film thickness, increase the minimum oil film thickness, improve lubrication, reduce wear, and at the same time, ensure the overall supporting role of the bearing assembly 400 on the crankshaft 300, thereby improving the reliability of the bearing assembly 400 and the rotary compressor.

[0066] Reference Figure 2 As shown, it can be understood that the height h1 of the first flexible structure 420 satisfies: 1.5mm ≤ h1 ≤ 20mm. When h1 is too small, the flexibility of the first flexible structure 420 is insufficient, failing to increase the contact area between the crankshaft 300 and the inner wall of the bearing body 410, resulting in a too small minimum oil film thickness, deterioration of the oil film thickness, increased wear, and even abnormal wear. When h1 is too large, the flexibility of the first flexible structure 420 increases, but the structural stiffness will decrease significantly. The first flexible structure 420 itself is prone to deformation, reducing the supporting force on the crankshaft 300, causing increased deformation of the crankshaft 300, and making it difficult to maintain the stability of the oil film thickness, i.e., the oil film thickness will deteriorate.

[0067] Reference Figure 7 As shown, it is easy to understand that under the same operating conditions, the minimum oil film thickness first increases and then decreases as the height h1 of the first flexible structure 420 increases. When 1.5mm ≤ h1 ≤ 20mm is satisfied, the minimum oil film thickness is greater than or equal to 1.3μm; when h1 < 1.5mm or h1 > 20mm, the minimum oil film thickness is less than 1.3μm. Therefore, making 1.5mm ≤ h1 ≤ 20mm, for example, h1 = 2mm, h1 = 5mm, h1 = 8mm, h1 = 12mm, or h1 = 17mm, can ensure that the first flexible structure 420 has sufficient flexibility to increase the contact area between the crankshaft 300 and the inner wall of the bearing body 410, thereby increasing the minimum oil film thickness, improving lubrication, and reducing wear. It can also prevent the first flexible structure 420 from having insufficient structural stiffness, which would lead to easy deformation and consequently deteriorate the oil film thickness, i.e., reduce the minimum oil film thickness. Therefore, making the minimum oil film thickness sufficiently large is necessary to improve lubrication.

[0068] Reference Figure 2As shown, it can be understood that, along the radial direction of the bearing body 410, the groove width of the annular groove 440 at the bottom is defined as B, satisfying: B≥1mm, that is, the minimum distance between the inner wall of the through hole 413 and the outer peripheral wall of the first flexible structure 420 is 1mm. It is easy to understand that when machining the first flexible structure 420 on the bearing body 410, it is usually necessary to cut between the inner wall of the through hole 413 and the outer peripheral wall of the first flexible structure 420 to machine the annular groove 440 or improve the dimensional accuracy of the annular groove 440, ensuring B≥1mm. This guarantees the feasibility of machining the annular groove 440, avoids the groove width being too small to allow for tool entry, and reduces machining difficulty.

[0069] Reference Figure 3 As shown, in some embodiments, it is understood that the bearing assembly 400 further includes a bushing 450, which is disposed in the shaft hole 430 and partially extends into the through hole 413. In this case, the upper end of the crankshaft 300 passes through the bushing 450. It is readily understood that the lower end of the bushing 450 is flush with the lower end of the shaft hole 430. The bearing body 410 is provided with a second flexible structure 460, which is an annular wall structure located at the end of the shaft hole 430 facing the through hole 413. The second flexible structure 460 is arranged around the bushing 450, and generally, the upper end of the second flexible structure 460 is flush with the upper end of the bushing 450. The outer peripheral wall of the second flexible structure 460 is spaced apart from the inner wall of the through hole 413. Therefore, an annular groove 440 is defined between the outer peripheral wall of the second flexible structure 460 and the inner wall of the through hole 413. The second flexible structure 460 and the part of the bushing 450 that extends into the through hole 413 are combined to form the first flexible structure 420. This can also increase the minimum oil film thickness and maintain the stability of the oil film thickness, and can avoid excessive surface pressure at the root 422, thus improving reliability. This will not be elaborated further here.

[0070] It is understood that the bushing 450 includes a friction-reducing coating, which is attached to the inner peripheral wall of the bushing 450. The friction-reducing coating can be a material such as polymer resin or graphite, thereby reducing the friction on the inner wall of the bushing 450, improving the lubrication between the crankshaft 300 and the bearing assembly 400, reducing wear, effectively extending the service life of the bearing assembly 400 and improving reliability, thereby improving the overall reliability of the rotary compressor.

[0071] The refrigeration device according to the second aspect of this utility model can be an electrical appliance such as an air conditioner or refrigerator, and includes a rotary compressor as described in any of the above embodiments.

[0072] Since the refrigeration equipment adopts all the technical solutions of the rotary compressor in the above embodiments, it has at least all the beneficial effects brought about by the technical solutions in the above embodiments.

[0073] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A rotary compressor, characterized in that, include: Pump body assembly, including cylinder; An electric motor assembly, comprising a stator and a rotor, wherein the stator is arranged around the rotor; A crankshaft passes through and is connected to the rotor, the crankshaft including an eccentric portion, the eccentric portion being rotatably disposed within the cylinder; A bearing assembly includes a bearing body and a first flexible structure. The bearing body has a shaft hole and a through hole, which are arranged axially and communicate with each other. The inner diameter of the through hole is larger than the inner diameter of the shaft hole. The bearing body is located on the side of the motor assembly away from the pump body assembly and is fitted onto the end of the crankshaft through the shaft hole. The first flexible structure is located at the end of the shaft hole near the through hole and is arranged around the crankshaft. The outer wall of the first flexible structure is spaced apart from the inner wall of the through hole and defines an annular groove. The outer wall of the first flexible structure is inclined. From the groove opening to the bottom of the annular groove, the thickness of the first flexible structure increases radially along the bearing body.

2. The rotary compressor according to claim 1, characterized in that: The first flexible structure and the bearing body are integrally formed.

3. The rotary compressor according to claim 2, characterized in that: The first flexible structure includes a head and a root. The root is connected to the bearing body. The head extends axially toward the bearing body and radially toward the bearing body. The minimum thickness at the end face of the head is T1, which satisfies: 1mm≤T1≤4mm.

4. The rotary compressor according to claim 3, characterized in that: Along the radial direction of the bearing body, the maximum thickness of the first flexible structure at the root is T2, and along the axial direction of the bearing body, the height of the first flexible structure is h1, satisfying: 0.09≤(T2-T1) / h1≤1, where T1<T2.

5. The rotary compressor according to claim 2, characterized in that: The inner diameter of the shaft hole is D, and the height of the first flexible structure along the axial direction of the bearing body is h1, satisfying: h1≤0.5D.

6. The rotary compressor according to claim 2, characterized in that: Along the axial direction of the bearing body, the height of the first flexible structure is h1, and the sum of the height of the first flexible structure and the height of the shaft hole is H, satisfying: h1 / H≤2 / 3.

7. The rotary compressor according to claim 2, 5 or 6, characterized in that: Along the axial direction of the bearing body, the height of the first flexible structure is h1, which satisfies: 1.5mm≤h1≤20mm.

8. The rotary compressor according to claim 1, characterized in that: Along the radial direction of the bearing body, the width of the annular groove at the bottom is B, which satisfies: B≥1mm.

9. The rotary compressor according to claim 1, characterized in that: The bearing assembly further includes a bushing, which is disposed in the shaft hole and partially extends into the through hole. The bearing body is provided with a second flexible structure, which is located at one end of the shaft hole near the through hole and arranged around the bushing. The part of the bushing extending into the through hole and the second flexible structure together form the first flexible structure.

10. The rotary compressor according to claim 9, characterized in that: The bushing includes a friction-reducing coating that is attached to the inner peripheral wall of the bushing.

11. A refrigeration device, characterized in that, Including the rotary compressor as described in any one of claims 1 to 10.

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