Crankshaft structure for compressor and compressor

Abstract

The utility model relates to the technical field of compressors, in particular to a crankshaft structure for a compressor and the compressor, the crankshaft structure for the compressor comprises a core part, and the hardness of the core part is H1; and an outer peripheral part formed on the outer periphery of the core part, the hardness of the outer peripheral part being H2, the hardness ratio of the hardness H2 of the outer peripheral part to the hardness H1 of the core part being h, 1.95 < h < 2.22 or 5.6 < = h < = 6.2. The crankshaft structure for the compressor and the compressor can solve the problem of how to improve the wear resistance of the matching part of the crankshaft.

Description

TECHNICAL FIELD

[0001] The present application relates to the compressor technical field, especially to a crankshaft structure for compressor and the compressor. BACKGROUND

[0002] The compressor with high rotating speed (rotating speed is above 100Hz) can reach the same capacity output as the high displacement structure design basically under the condition of lower displacement structure design, and is smaller in size and lower in cost, and is widely used in the refrigeration industry at present.

[0003] But under the condition of high rotating speed, the motor generates greater centrifugal force when running, which causes the crankshaft to be worn at the position matched with other components of the compressor due to the centrifugal force during operation, thereby affecting the service life of the compressor.

[0004] At present, the technical scheme of adding or improving the lubricating oil passage on the crankshaft is generally adopted in the industry to enhance the lubricating effect of the bearing part. However, this solution not only increases the design cost, but also significantly improves the complexity of the processing technology. Therefore, the optimization design of the wear resistance of the matched part of the crankshaft and the related components has become a technical problem to be solved at present. CONTENT OF THE INVENTION

[0005] Therefore, the purpose of the present application is to provide a crankshaft structure for compressor and the compressor to solve the problem of how to improve the wear resistance of the matched part of the crankshaft.

[0006] According to the first aspect of the present application, a crankshaft structure for compressor is provided, wherein the crankshaft structure for compressor comprises: a core portion, the hardness of the core portion is H1; an outer peripheral portion formed on the outer periphery of the core portion, the hardness of the outer peripheral portion is H2, and the hardness ratio of the hardness H2 of the outer peripheral portion to the hardness H1 of the core portion is h, 1.95

[0007] Preferably, when the material of the core portion is steel, the outer peripheral portion is formed by surface quenching treatment of the core portion, and in this case, the hardness ratio is 1.95

[0008] Preferably, the thickness of the outer peripheral portion is d, and 0.8mm≤d.

[0009] Preferably, the crankshaft structure for the compressor comprises: a crankshaft body, which is sequentially provided with an eccentric portion, a main bearing portion, a main shaft portion and a lower bearing portion from top to bottom along an axial direction; and bearings, which are respectively installed on the outer periphery of the eccentric portion, the main bearing portion and the lower bearing portion.

[0010] Preferably, the crankshaft body is formed with the outer peripheral portion at the eccentric portion, the main bearing portion and the lower bearing portion.

[0011] Preferably, the outer peripheral portion formed at the eccentric portion has a thickness d1, 0.8mm≤d1≤2.5mm, and a ratio of d1 to the radius of the eccentric portion is 3.5% to 16.7%.

[0012] Preferably, the bearing comprises: a bushing, which is sleeved on the crankshaft body; and an inner surface coating, which is arranged on the side of the bushing close to the crankshaft body, and a ratio of the elastic modulus E1 of the inner surface coating to the elastic modulus E2 of the outer peripheral portion is E, 0.24%<E<0.26%.

[0013] Preferably, the thickness D of the inner surface coating satisfies: 0.12mm≤D≤0.4mm.

[0014] Preferably, the thickness of the inner surface coating is D1, 0.2mm≤D1≤0.23mm.

[0015] According to the second aspect of the present application, a compressor is provided, wherein the compressor comprises the crankshaft structure for the compressor as described above.

[0016] The crankshaft structure for the compressor and the compressor of the present application comprise a core portion and an outer peripheral portion formed on the outer periphery of the core portion. The hardness of the core portion is H1, and the hardness of the outer peripheral portion is H2. The hardness ratio of the hardness H2 of the outer peripheral portion to the hardness H1 of the core portion is h, 1.95<h<2.22 or 5.6≤h≤6.2. In this way, by arranging the outer peripheral portion with higher hardness on the outer periphery of the core portion, the wear resistance of the matching portion of the crankshaft body and the bearing can be significantly improved, thereby effectively reducing the wear of the crankshaft body during the operation of the compressor. Thus, the problem of how to improve the wear resistance of the matching portion of the crankshaft can be effectively solved.

[0017] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as limiting the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of the drawings.

[0019] Figure 1 is a schematic view of a crankshaft structure for a compressor according to the present application.

[0020] Figure 2 is a schematic view of a crankshaft structure for a compressor according to the present application. Figure 1 is a sectional view of A-A.

[0021] Figure 3 is a schematic view of a crankshaft structure for a compressor and a partial structure of a compressor according to the present application.

[0022] Figure 4 is a schematic view of a crankshaft structure for a compressor and another partial structure of a compressor according to the present application.

[0023] Reference signs: 1 - crankshaft main body; 11 - eccentric portion; 12 - main bearing portion; 13 - main shaft portion; 14 - lower bearing portion; 2 - bearing; 3 - oil hole; 100 - core portion; 200 - outer peripheral portion. DETAILED DESCRIPTION

[0024] The following detailed description is provided to help the reader obtain a complete understanding of the methods, devices, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, devices, and / or systems described herein will be apparent after an understanding of the disclosure of the present application. For example, the order of the operations described herein is merely an example, and the order is not limited to the order set forth herein, but, except for operations that must occur in a specific order, changes that will be apparent after an understanding of the disclosure of the present application can be made. In addition, the description of features known in the art can be omitted in order to improve clarity and conciseness.

[0025] The features described herein can be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to show some of the many ways in which the methods, devices, and / or systems described herein can be implemented after an understanding of the disclosure of the present application.

[0026] Throughout the specification, when an element (such as a layer, region or substrate) is referred to as being "on" another element, "connected to" another element, "coupled to" another element, "adjacent to" another element, "on top of" another element, or "covering" another element, it can be directly on, connected to, coupled to, adjacent to, on top of, or covering the other element, or one or more other elements can be interposed therebetween. In contrast, when an element is referred to as being "directly on", "directly connected to", "directly coupled to", "directly adjacent to", "directly on top of", or "directly covering" another element, there are no other elements interposed therebetween.

[0027] As used herein, the term "and / or" includes any one of the listed items and any combination of two or more of the listed items.

[0028] Although terms such as "first", "second", and "third" can be used herein to describe various components, assemblies, regions, layers or sections, these components, assemblies, regions, layers or sections are not limited by these terms. Rather, these terms are only used to distinguish one component, assembly, region, layer or section from another component, assembly, region, layer or section. Thus, a component, assembly, region, layer or section referred to as a first component, assembly, region, layer or section in one example described herein can also be referred to as a second component, assembly, region, layer or section in another example without departing from the teachings of the examples.

[0029] For ease of description, spatial relationship terms, such as "on", "upper", "beneath", and "lower", can be used herein to describe one element's relationship to another element as illustrated in the figures. Such spatial relationship terms can be intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, a component described as on "top" or the "upper" of another component would then be oriented on the "bottom" or "lower" of the other component. Accordingly, the term "on" encompasses both a "on" and "under" orientation in accordance with the spatial orientation of the device. The device can be oriented in other ways (e.g., rotated 90 degrees or at other orientations) and an appropriate modification to the spatial relationship terminology would be made to accommodate those orientations.

[0030] The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of examples. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," "including" and "has" or "having" and the like are inclusive of the stated features, numbers, operations, members, elements and / or the like, but do not exclude the presence or addition of one or more other features, numbers, operations, members, elements and / or the like.

[0031] Variations in the shapes illustrated in the drawings can occur as a result of manufacturing processes and / or tolerances. Thus, the examples described herein are not limited to the specific shapes illustrated in the drawings, but include variations in shapes that occur during manufacturing.

[0032] Features of the examples described herein can be combined with one another as would be apparent to one of ordinary skill in the art after understanding the disclosure provided herein. Furthermore, although examples are described as having various configurations, other configurations can also be utilized as would be apparent to one of ordinary skill in the art after understanding the disclosure provided herein.

[0033] As Figures 1 to 4 indicated, a crankshaft structure for a compressor according to a first aspect of the present application includes a core portion 100 and an outer peripheral portion 200.

[0034] In the following description, reference is made to the Figures 1 to 4 The specific structure of the above components of the crankshaft structure for a compressor and the connection relationship of the above components are described in detail.

[0035] As Figures 1 to 4 indicated, in the embodiment, the outer peripheral portion 200 can be formed on the outer periphery of the core portion 100, so that other parts in the compressor cooperate with the outer peripheral portion 200 to avoid the core portion 100 from being directly worn. The hardness of the core portion 100 can be H1, and the hardness of the outer peripheral portion 200 can be H2. The hardness ratio of the hardness H2 of the outer peripheral portion 200 to the hardness H1 of the core portion 100 can be h, 1.95 < h < 2.22 or 5.6 < h < 6.2. In this way, by arranging the outer peripheral portion 200 with higher hardness on the outer periphery of the core portion 100, the wear resistance of the crankshaft structure for a compressor can be significantly improved, and thus the service life of the compressor can be improved.

[0036] Further, preferably, as Figures 1 to 4As shown, in this embodiment, the hardness ratio h can correspond to different value ranges depending on the material of the core 100. Specifically, when the core 100 is made of steel (e.g., 45 steel), the outer peripheral portion 200 is formed by surface hardening of the core 100. In this case, the hardness ratio h is 1.95 < h < 2.22. The hardness of the outer periphery of the core 100 can change from 28 HRC (corresponding to H1) to 55 HRC to 62 HRC (corresponding to H2). When the core 100 is made of chromium (e.g., 20Cr), the outer peripheral portion 200 is formed by surface carburizing of the core 100. In this case, the hardness ratio h is 5.6 ≤ h ≤ 6.2. The hardness of the outer periphery of the core 100 can change from 10 HRC (corresponding to H1) to 56 HRC to 62 HRC (corresponding to H2).

[0037] In this embodiment, when the core 100 is made of steel and h ≥ 2.22, or when the core 100 is made of chromium and h > 6.2, the outer peripheral portion 200 will experience microcrack propagation due to excessive hardness, leading to cracking or peeling. Conversely, when the core 100 is made of steel and h ≤ 1.95, or when the core 100 is made of chromium and h < 5.6, the outer peripheral portion 200 will lack sufficient hardness, making it difficult to effectively reduce wear and affecting the compressor's service life. Therefore, when the hardness ratio h is within the range of 1.95 < h < 2.22 and 5.6 ≤ h ≤ 6.2, the outer peripheral portion 200 can effectively reduce wear.

[0038] Preferred, such as Figures 1 to 4 As shown in the embodiment, the crankshaft structure for the compressor may include a crankshaft body 1 and bearings 2. The crankshaft body 1 may be provided axially from top to bottom with an eccentric portion 11, a main bearing portion 12, a main shaft portion 13, and a lower bearing portion 14. There may be multiple bearings 2, which may be respectively installed on the outer periphery of the eccentric portion 11, the main bearing portion 12, and the lower bearing portion 14. The types of the multiple bearings 2 may be different. The bearings 2 installed on the outer periphery of the eccentric portion 11 may be sliding bearings, which can form a stable oil film at high speeds to provide good lubrication and reduce friction and wear.

[0039] Preferred, such as Figure 1 and Figure 2As shown, in this embodiment, the eccentric portion 11, the main bearing portion 12, the main shaft portion 13, and the lower bearing portion 14 can all be formed as cylindrical structures. This allows the outer peripheral portion 200 to be formed only on the circumferential surface of the eccentric portion 11, the main bearing portion 12, the main shaft portion 13, or the lower bearing portion 14. With this configuration, the outer peripheral portion 200 covers the radially outer side of the core portion 100, and the oil hole 3 can be formed within the core portion 100. It is worth noting that... Figure 2 The content is for illustrative purposes only. In actual processing, due to process reasons, the boundary line between the outer peripheral portion 200 and the core portion 100 will be non-uniform and linear. The outer peripheral portion 200 will extend radially (microscopically) from the outside to the inside of the core portion 100.

[0040] Further optimized, such as Figure 3 and Figure 4 As shown in the embodiment, to reduce processing time and lower processing costs, the outer peripheral portion 200 can be provided only at the eccentric portion 11, the main bearing portion 12, and the lower bearing portion 14 of the crankshaft body 1. That is, in actual production, surface hardening or surface carburizing treatment can be performed only on the part of the crankshaft body 1 used to install the bearing 2, thereby avoiding waste of time and cost.

[0041] Preferred, such as Figure 1 and Figure 2 As shown, in this embodiment, the thickness of the outer peripheral portion 200 is d, where 0.8 mm ≤ d. This design ensures that the outer peripheral portion 200 can effectively reduce wear during compressor operation.

[0042] Furthermore, preferably, such as Figures 1 to 3 As shown, in this embodiment, the thickness of the outer peripheral portion 200 formed at the eccentric portion 11 can be d1, where 0.8mm ≤ d1 ≤ 2.5mm. Specifically, in a scroll compressor, centrifugal force is generated when the moving disc rotates eccentrically around the center of the stationary disc. This centrifugal force increases the contact pressure between the moving disc and the eccentric portion 11, thereby exacerbating the wear of the eccentric portion 11. Simultaneously, the centrifugal force also causes uneven distribution of the lubricating oil film, further intensifying the wear of the eccentric portion 11. Therefore, the eccentric portion 11 requires a longer surface hardening or carburizing treatment so that the thickness of the outer peripheral portion 200 at the eccentric portion 11 is greater than the thickness of the outer peripheral portions 200 of other parts of the crankshaft body 1, thereby extending the overall service life of the crankshaft body 1.

[0043] However, when the thickness d1 of the outer peripheral portion 200 is greater than 2.5 mm, the eccentric portion 11 is subjected to an excessively long surface quenching treatment or surface carburizing treatment. Thus, not only time and material costs are consumed, but also the hardness of the outermost portion of the outer peripheral portion 200 is excessively high, which causes the surface of the eccentric portion 11 to crack, thereby affecting the performance of the crankshaft body 1.

[0044] Preferably, as shown in the embodiments, the diameter of the eccentric portion 11 can be 30 mm to 45 mm (may be 30 mm, 35 mm, 38 mm or 45 mm), and the ratio of the thickness d1 of the outer peripheral portion 200 to the radius of the eccentric portion 11 can be 3.5% to 16.7%. Thus, the surface hardness of the eccentric portion 11 can meet the requirement of reducing wear and will not be excessively high to cause cracking. Figures 1 to 3

[0045] Preferably, as shown in the embodiments, the diameter of the eccentric portion 11 can be 30 mm to 45 mm (may be 30 mm, 35 mm, 38 mm or 45 mm), and the ratio of the thickness d1 of the outer peripheral portion 200 to the radius of the eccentric portion 11 can be 3.5% to 16.7%. Thus, the surface hardness of the eccentric portion 11 can meet the requirement of reducing wear and will not be excessively high to cause cracking. Figures 1 to 4

[0046] Thus, the service life of the bearing 2 can be improved, and the stability of the crankshaft body 1 can be improved. Specifically, a lower elastic modulus can enable the bearing 2 to have a certain elastic deformation capacity when bearing a load, thereby dispersing stress and prolonging the service life, and a lower elastic modulus can improve the wear resistance of the bearing 2. The crankshaft body 1 needs to bear a large centrifugal force, torque and other stress, and thus needs to have a higher elastic modulus to ensure the stability of the crankshaft body 1 under various working conditions. Thus, when the ratio E of the elastic modulus is kept at 0.24% < E < 0.26%, the stability of the crankshaft body 1 can be ensured, and the wear resistance of the bearing 2 can be improved.

[0047] Preferably, in the embodiments, the bushing can be a metal bushing (for example, a steel material or other metal material with higher rigidity), and the inner surface coating can be a mixed coating of polytetrafluoroethylene (PTFE) and metal (wherein the metal part can be copper or aluminum in a porous state formed after high-temperature sintering, so that the PTFE can be rolled into the micropores). The polytetrafluoroethylene material has a low friction characteristic and can optimize the material strength and stability, and can further reduce the wear of the crankshaft body 1 in cooperation with the hardened crankshaft body 1. In addition, the metal material part in the inner surface coating can further reduce friction, which absorbs the friction force and centrifugal force to reduce the force transmitted to the bushing.​​

[0048] Further, preferably, the thickness of the inner surface coating layer can be D1, and 0.2 mm≤D1≤0.23 mm. In this way, when the thickness D1 of the inner surface coating layer is greater than or equal to 0.2 mm, the alloy material can be prevented from being exposed to the surface and the crankshaft body 1 from being abraded, and when the thickness D1 of the inner surface coating layer is less than or equal to 0.23 mm, the radial installation size can be ensured to prevent the problem of being unable to be installed due to the inner surface coating layer being too thick.

[0049] The specific embodiments are verified as follows:

[0050] The life experiment conditions are as follows: the suction pressure is 0.17 MPa (G), the exhaust pressure is 3.83 MPa (G), and the operation time is 500 h.

[0051] The roughness test standard and method are as follows: the test method and standard of GB / T 3505-2000 are adopted.

[0052] Comparative Example 1: When the material of the crankshaft body 1 is 45 steel, no surface quenching treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0053] Comparative Example 2: When the material of the crankshaft body 1 is 20Cr, no surface carburizing treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0054] Example 1: When the material of the crankshaft body 1 is 45 steel, surface quenching treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0055] Example 2: When the material of the crankshaft body 1 is 45 steel, surface quenching treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0056] Example 3: When the material of the crankshaft body 1 is 45 steel, surface quenching treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0057] Example 4: When the material of the crankshaft body 1 is 20Cr, surface carburizing treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0058] Example 5: When the material of the crankshaft body 1 is 20Cr, surface carburizing treatment is performed, and the roughness of each position is tested after finishing, and then the life experiment is performed.

[0059]

[0060] Therefore, it can be concluded that when the hardness ratio h adopts the value range of 1.95 < h < 2.22 and 5.6 ≤ h ≤ 6.2, the outer peripheral portion 200 can effectively play a function of reducing wear.

[0061] In addition, as Figures 3 to 4 The compressor comprises the crankshaft structure for compressor as described above.

[0062] In use, the crankshaft structure for compressor significantly improves the wear resistance of the crankshaft body 1 by setting the outer peripheral portion 200 with higher hardness on the outer periphery of the core portion 100, thereby effectively reducing the wear of the crankshaft body 1 during the operation of the compressor, and improving the service life of the compressor.

[0063] Finally, it should be noted that: the above-described embodiments are merely specific embodiments of the present application, which are used to illustrate the technical solutions of the present application, but not to limit them, the protection scope of the present application is not limited to this, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: any person skilled in the art within the technical range disclosed by the present application, they can still modify or easily think of changes to the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications, changes or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A crankshaft structure for a compressor, disposed in the compressor, characterized in that, The crankshaft structure for the compressor includes: The core has a hardness of H1. The outer peripheral portion is formed on the outer periphery of the core portion. The hardness of the outer peripheral portion is H2. The hardness ratio of the hardness H2 of the outer peripheral portion to the hardness H1 of the core portion is h, where 1.95 < h < 2.22 or 5.6 ≤ h ≤ 6.

2.

2. The crankshaft structure for a compressor according to claim 1, characterized in that, When the core is made of steel, the outer periphery is formed by surface hardening of the core. In this case, the hardness ratio is 1.95 < h < 2.

22. When the core material is chromium, the outer periphery is formed by carburizing the core surface. In this case, the hardness ratio is 5.6≤h≤6.

2.

3. The crankshaft structure for a compressor according to claim 2, characterized in that, The thickness of the outer periphery is d, where 0.8 mm ≤ d.

4. The crankshaft structure for a compressor according to claim 2, characterized in that, The crankshaft structure for the compressor includes: A crankshaft body, wherein the crankshaft body is provided with an eccentric part, a main bearing part, a main shaft part, and a lower bearing part sequentially arranged from top to bottom along the axial direction; and The bearings, a plurality of the bearings, are respectively mounted on the outer periphery of the eccentric portion, the main bearing portion and the lower bearing portion.

5. The crankshaft structure for a compressor according to claim 4, characterized in that, The crankshaft body has the outer peripheral portion formed at the eccentric portion, the main bearing portion, and the lower bearing portion.

6. The crankshaft structure for a compressor according to claim 4, characterized in that, The thickness of the outer periphery formed at the eccentric portion is d1, 0.8 mm ≤ d1 ≤ 2.5 mm, and the ratio of d1 to the radius of the eccentric portion is 3.5% to 16.7%.

7. The crankshaft structure for a compressor according to any one of claims 4 to 6, characterized in that, The bearing includes: Bushing, fitted onto the crankshaft body; and An inner surface coating is provided on the side of the bushing near the crankshaft body, and the ratio of the elastic modulus E1 of the inner surface coating to the elastic modulus E2 of the outer periphery is E, 0.24% < E < 0.26%.

8. The crankshaft structure for a compressor according to claim 7, characterized in that, The thickness D of the inner surface coating satisfies: 0.12mm≤D≤0.4mm.

9. The crankshaft structure for a compressor according to claim 8, characterized in that, The thickness of the inner surface coating is D1, where 0.2mm ≤ D1 ≤ 0.23mm.

10. A compressor, characterized in that, The compressor includes a crankshaft structure for a compressor according to any one of claims 1 to 9.

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