Crankshaft and rolling piston compressor having the same

Abstract

The application provides a crankshaft and a rolling rotor compressor with the crankshaft, the crankshaft comprises a long shaft section and a short shaft section, an outer circumferential surface of at least one of the long shaft section and the short shaft section is provided with an oil supply micro groove; the oil supply micro groove comprises a first micro groove and a second micro groove, the first micro groove and the second micro groove are sequentially arranged along an axial direction of the crankshaft; an extension direction of the first micro groove intersects with the axial direction of the crankshaft, an extension direction of the second micro groove is opposite to that of the first micro groove; a central oil hole is arranged in the crankshaft and extends along the axial direction of the crankshaft, and one side of the oil supply micro groove is provided with an oil outlet hole which is communicated with the central oil hole. The oil supply micro groove is arranged on the outer surface of the crankshaft, can simultaneously play the oil pumping and oil returning roles, can ensure that the bearing is fully lubricated, can effectively control the oil discharge rate, and can ensure that the compressor pump body is stably and reliably operated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of compressors, in particular to a crankshaft and a rolling rotor compressor having the same. BACKGROUND

[0002] To ensure good lubrication of the crankshaft and bearing pair in the rolling rotor compressor, an oil groove is generally formed on the inner surface of the bearing, and the lubricating oil is distributed to the friction surface of the crankshaft and bearing through the oil groove by the pumping effect of the crankshaft rotation. However, with the development demand for miniaturization and high speed of the compressor, the oil injection amount of the pump body is reduced, the rotating speed is increased, the oil discharge rate of the compressor is increased, and the oil return is reduced, which causes the pump body to be out of oil or even locally out of oil, and seriously affects the reliability of the parts.

[0003] In addition, the oil groove is usually formed in the non-load-bearing area of the bearing to avoid excessive weakening of the oil film carrying capacity, but the range of the non-load-bearing area is difficult to accurately determine, and the non-load-bearing area greatly limits the design of the slot position interval and the slot angle, causing problems such as limited amount of lubricating oil, deteriorated lubrication conditions, and insufficient oil film carrying capacity. SUMMARY

[0004] To solve the problem of increased oil discharge rate and deteriorated lubrication of the compressor and ensure sufficient lubrication of the crankshaft and bearing, the present application provides a crankshaft and a rolling rotor compressor having the same.

[0005] According to one aspect of the present application, a crankshaft is provided, comprising a long shaft section and a short shaft section, and an oil supply micro groove is arranged on the outer circumferential surface of at least one of the long shaft section and the short shaft section.

[0006] The oil supply micro groove comprises a first micro groove and a second micro groove, and the first micro groove and the second micro groove are arranged in sequence along the axial direction of the crankshaft.

[0007] The extension direction of the first micro groove intersects the axial direction of the crankshaft, and the extension direction of the second micro groove is opposite to that of the first micro groove.

[0008] The crankshaft is provided with a central oil hole extending in the axial direction thereof, and one side of the oil supply micro groove is provided with an oil outlet hole communicating with the central oil hole.

[0009] Further, the number of oil supply micro grooves is multiple, and the oil supply micro grooves are distributed at intervals along the circumferential direction of the crankshaft, and a groove table is formed between adjacent two oil supply micro grooves.

[0010] Further, the width of the oil supply micro groove is w, the sum of the width of the oil supply micro groove and the width of the groove table is t, and w / t is set to 0.1-0.9.

[0011] Further, a groove dam is formed between the first micro groove and the second micro groove.

[0012] Further, the length of the oil supply micro groove in the axial direction of the crankshaft is L, the length of the first micro groove in the axial direction of the crankshaft is g1, the length of the second micro groove in the axial direction of the crankshaft is g2, and (g1+g2) / L is set to 0.2-1.

[0013] Further, the first micro groove extends away from the second micro groove in a direction away from the rotation direction of the crankshaft.

[0014] Further, the angle between the extension direction of the first micro groove and the axial direction of the crankshaft is 10-80°.

[0015] Further, the depth of the oil supply micro groove is 2-50 μm.

[0016] Further, the linear shape of the first micro groove or / and the second micro groove comprises a straight line, a curved line or a spiral line.

[0017] Further, a plurality of the oil supply micro grooves distributed along the circumferential direction of the crankshaft form a micro groove group, and a plurality of the micro groove groups are arranged along the axial direction of the crankshaft.

[0018] The application also relates to a rolling rotor compressor comprising a crankshaft, wherein the crankshaft is the crankshaft according to any one of the above.

[0019] According to the technical scheme of the application, the oil supply micro groove is arranged on the outer surface of the fitting section of the crankshaft, the oil supply micro groove comprises the first micro groove and the second micro groove with opposite extension directions, the first micro groove functions as an oil pump, the second micro groove functions as an oil return, the bearing is fully lubricated, the oil discharge rate is effectively controlled, and the compressor pump body is stably and reliably operated. The micro groove is arranged on the outer surface of the crankshaft, the inner surface of the corresponding bearing can be free of the oil groove design, and the problem of the position distribution and the groove angle design limitation of the bearing inner surface oil groove in the non-load bearing area is avoided. The pumping effect and the stepped dynamic pressure effect of the micro groove can improve the fluid film bearing capacity, ensure the sufficient lubrication between the crankshaft and the bearing, and avoid the contact wear. The micron-level depth design of the micro groove does not damage the oil film bearing capacity, ensures the reliable lubrication, and the pumping effect and the stepped dynamic pressure effect of the micro groove can improve the fluid film bearing capacity, ensure the sufficient lubrication between the crankshaft and the bearing, and avoid the contact wear. BRIEF DESCRIPTION OF DRAWINGS

[0020] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application, serve to explain the application, and do not constitute an improper limitation on the application.

[0021] Figure 1 FIG. 1 is a structural schematic view of a rolling rotor compressor according to an embodiment of the application;

[0022] Figure 2 Structure diagram of the crankshaft of the first embodiment of the present application;

[0023] Figure 3 Structure diagram of the oil supply micro groove of the first embodiment of the present application;

[0024] Figure 4 Principle diagram of the oil supply micro groove of the first embodiment of the present application;

[0025] Figure 5 Structure diagram of the crankshaft of the second embodiment of the present application;

[0026] Figure 6 Structure diagram of the crankshaft of the third embodiment of the present application;

[0027] Figure 7 Structure diagram of the crankshaft of the fourth embodiment of the present application;

[0028] Wherein:

[0029] 1 - crankshaft; 2 - main bearing; 3 - auxiliary bearing; 11 - long shaft section; 12 - short shaft section; 13 - central oil hole; 14 - oil outlet hole; 15 - eccentric part; 20 - oil supply micro groove; 21 - first micro groove; 22 - second micro groove; 23 - groove table; 24 - groove dam; 210 - first micro groove group; 220 - second micro groove group. DETAILED DESCRIPTION

[0030] The present application will be described in detail below with reference to the accompanying drawings and embodiments, and it should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0031] It should be pointed out that the following detailed description is exemplary and is intended to provide further description of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0032] It should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, there is a presence of the features, steps, operations, devices, components and / or combinations thereof.

[0033] In order to solve the problems of increased oil discharge rate of the compressor and deteriorated lubrication, and to ensure sufficient lubrication of the crankshaft and the bearing, the present application provides a crankshaft and a rolling rotor type compressor with the crankshaft.

[0034] Example 1

[0035] like Figure 1 As shown, the rolling rotor compressor of this embodiment mainly includes a crankshaft 1, a main bearing 2 and a secondary bearing 3. The inner surface of the main bearing 2 is sleeved on the long shaft section 11 of the crankshaft 1, and the inner surface of the secondary bearing 3 is sleeved on the short shaft section 12 of the crankshaft 1. Two eccentric parts 15 are provided between the long shaft section 11 and the short shaft section 12, corresponding to a dual rotor compressor.

[0036] like Figure 2 As shown, an oil supply micro-groove 20 is provided on the long shaft section 11 of the crankshaft 1, and a central oil hole 13 is provided in the center of the crankshaft 1 along its axial direction. A radial oil outlet hole 14 is provided on one side of the oil supply micro-groove 20, and the oil outlet hole 14 is connected to the central oil hole 13.

[0037] The oil supply micro-groove 20 includes a first micro-groove 21 and a second micro-groove 22 arranged sequentially along the axial direction of the crankshaft 1. The extension directions of the first micro-groove 21 and the second micro-groove 22 are both intersecting the axial direction of the crankshaft 1, and the extension direction of the first micro-groove 21 is opposite to the extension direction of the second micro-groove 22.

[0038] To further improve the lubrication effect of the oil supply microgrooves 20, multiple oil supply microgrooves 20 are provided and distributed at intervals along the circumferential direction of the crankshaft 1, forming a microgroove group that circles the central axis of the crankshaft 1.

[0039] Specifically, the micro-groove group consisting of multiple first micro-grooves 21 is the first micro-groove group 210, which is located near the eccentric part 15, and the micro-groove group consisting of multiple second micro-grooves 22 is the second micro-groove group 220, which is located away from the eccentric part 15, and the oil outlet 14 is located on the side of the first micro-groove group 210 near the eccentric part 15.

[0040] Optional, such as Figure 3 As shown, the angle between the extension direction of the first microgroove 21 and the second microgroove 22 and the axial direction of the crankshaft 1 is α, and its value ranges from 10 to 80°. In this embodiment, the value is 30°.

[0041] like Figure 3 As shown, a groove platform 23 is formed between two adjacent oil supply micro-grooves 20. That is, there is a groove platform 23 between two adjacent first micro-grooves 21 and between two adjacent second micro-grooves 22. It should be noted that the groove platform 23 is a spacer structure left on the outer surface of the crankshaft 1 due to the micro-grooving process, and it does not protrude from the outer surface of the crankshaft 1.

[0042] To improve lubrication, the oil supply micro-groove 20 has a certain width ratio to the groove platform 23. Specifically, the first micro-groove 21 will be used as an example for explanation. Figure 3In the embodiment, the width of the first micro groove 21 is w, the sum of the width of the first micro groove 21 and the width of the groove table 23 is t, and w / t can be set to 0.1-0.9, and in the embodiment, w / t is 0.5.

[0043] As shown in Figure 2 , the first micro groove 21 and the second micro groove 22 are arranged at intervals, so that the groove dam 24 is formed between the first micro groove group 210 and the second micro groove group 220, and similarly, the groove dam 24 is also an interval structure left on the outer surface of the crankshaft 1 due to micro groove processing, which does not protrude from the outer surface of the crankshaft 1.

[0044] In order to enhance the control of the oil discharge rate and improve the lubrication effect, the first micro groove 21, the second micro groove 22 and the groove dam 25 have a certain length ratio, and specifically, as shown in Figure 3 , the length of the entire oil supply micro groove 20 in the axial direction of the crankshaft 1 is L, the length of the first micro groove 21 in the axial direction of the crankshaft 1 is g1, the length of the second micro groove 22 in the axial direction of the crankshaft 1 is g2, and (g1+g2) / L can be set to 0.2-1, and when the value is 1, it means that the first micro groove 21 and the second micro groove 22 are connected and there is no groove dam 24 in between.

[0045] As can be easily understood, the total length L of the oil supply micro groove 20 should not be greater than the corresponding bearing height.

[0046] In order to ensure the pump oil return effect of the oil supply micro groove 20, the running direction of the first micro groove 21 and the second micro groove 22 needs to be opposite to the rotation direction of the crankshaft 1, and specifically, for the first micro groove 21, the direction in which the first micro groove 21 extends from the side away from the second micro groove 22 to the other side thereof is opposite to the rotation direction of the crankshaft 1, that is, as an example, Figure 2 , the direction in which the first micro groove 21 extends from the side close to the eccentric part 15 to the other side away from the eccentric part 15 is opposite to the rotation direction of the crankshaft 1, and corresponding to Figure 3 , the running direction of the first micro groove 21 is from left to right, and the rotation direction of the crankshaft 1 is from right to left.

[0047] Since the extension direction of the second micro groove 22 is opposite to that of the first micro groove 21, after the running direction of the first micro groove 21 is determined, the running direction of the second micro groove 22 is correspondingly determined.

[0048] As can be easily understood, when the oil outlet hole 14 is arranged on one side of the first micro groove 21, the first micro groove 21 functions as a pump, and the second micro groove 22 functions as a return; when the oil outlet hole 14 is arranged on one side of the second micro groove 22, the second micro groove 22 functions as a pump, and the first micro groove 21 functions as a return.

[0049] In order to make the micro groove generate step dynamic pressure effect while supplying oil, the depth of the oil supply micro groove 20 is set to 2-50 μm, that is, the depth of the first micro groove 21 and the second micro groove 22 is set to 2-50 μm.

[0050] In the embodiment, the shapes of the first micro groove 21 and the second micro groove 22 are not required, and the linear shapes thereof include but are not limited to straight lines, curves or helical lines.

[0051] By using the technical solution of the embodiment, the outer surface of the long axis section 11 of the crankshaft 1 is provided with the first micro groove group 210 and the second micro groove group 220, the fluid medium is axially pumped along the central oil hole 13 of the crankshaft 1 and flows out from the radial oil outlet hole 14, and the fluid medium is pumped to the bearing surface of the crankshaft 1 by the first micro groove group 210 to achieve the oil supply effect, accompanied by the circumferential shearing action and the axial pressure difference of the crankshaft 1. When the fluid medium flows along the first micro groove group 210 to the second micro groove 220, the second micro groove group 220 is opposite to the first micro groove group 210, and the second micro groove group 220 plays a reverse pumping role, that is, a back oil effect. That is, the first micro groove group 210 plays a role of pumping oil, and the second micro groove group 220 plays a role of back oil. In this way, the bearing can be fully lubricated, and the oil discharge rate can be effectively controlled, so as to ensure the stable and reliable operation of the compressor pump body.

[0052] Meanwhile, the micron-level depth of the first micro groove 21 and the second micro groove 22 does not destroy the oil film bearing capacity, ensures reliable lubrication, and along the flow direction of the fluid medium, at the groove table 23 and the groove dam 25, due to the convergence of the lubrication gap, a significant step dynamic pressure effect generates a local high pressure, as shown in Figure 4 , which further improves the overall bearing capacity of the oil film, ensures the reliability of lubrication, avoids problems such as oil film rupture caused by changes in operating conditions or external disturbances during work, reduces contact wear failure, and can further realize refrigerant lubrication to achieve an oil-free compressor design.

[0053] In addition, compared with the traditional oil groove on the inner surface of the bearing, the micro groove on the outer surface of the crankshaft reduces the machining difficulty and avoids the problem of design limitation of the position distribution and groove angle of the oil groove on the inner surface of the bearing in the non-bearing area.

[0054] Embodiment Two

[0055] This embodiment only describes the differences from Embodiment One, specifically, the first micro groove group 210 and the second micro groove group 220 are connected, and there is no groove dam 24 in the middle. The other components and principles are the same as those of Embodiment One, and will not be described here.

[0056] Embodiment Three

[0057] The embodiment only describes the difference from the first embodiment, specifically, the micro groove structure formed by the first micro groove group 210 and the second micro groove group 220 is provided as two and is spaced along the axial direction of the crankshaft 1, and other components and principles are the same as those of the first embodiment, which will not be described here.

[0058] Embodiment four

[0059] The embodiment only describes the difference from the first embodiment, specifically, the short shaft section 12 of the crankshaft 1 is also provided with the first micro groove group 210 and the second micro groove group 220, and other components and principles are the same as those of the first embodiment, which will not be described here.

[0060] In the description of the present application, it should be understood that the terms "center", "front, back, up, down, left, right", "transverse, vertical, perpendicular, horizontal" and "top, bottom" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate and imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the scope of protection of the present application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.

[0061] In the description of the present application, it should be noted that unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances

[0062] In addition, it should be noted that the use of "first", "second" and the like to limit parts is only for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, therefore cannot be understood as a limitation on the scope of protection of the present application.

[0063] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A crankshaft comprising a long shaft section (11) and a short shaft section (12), characterized in that: An oil supply micro groove (20) is arranged on an outer circumferential surface of at least one of the long shaft section (11) and the short shaft section (12). The oil supply micro groove (20) comprises a first micro groove (21) and a second micro groove (22), which are arranged in sequence in the axial direction of the crankshaft. The extension direction of the first micro groove (21) is intersected with the axial direction of the crankshaft, and the extension direction of the second micro groove (22) is opposite to the extension direction of the first micro groove (21). The crankshaft is provided with a central oil hole (13) extending in the axial direction thereof, and one side of the oil supply micro groove (20) is provided with an oil outlet hole (14) communicating with the central oil hole (13). The number of the oil supply micro grooves (20) is multiple, and the oil supply micro grooves (20) are distributed in the circumferential direction of the crankshaft, and a groove table (23) is formed between adjacent two oil supply micro grooves (20). The width of the oil supply micro groove (20) is w, the sum of the width of the oil supply micro groove (20) and the width of the groove table (23) is t, and w / t is set to 0.1-0.

9. The length of the oil supply micro groove (20) in the axial direction of the crankshaft is L, the length of the first micro groove (21) in the axial direction of the crankshaft is g1, the length of the second micro groove (22) in the axial direction of the crankshaft is g2, and (g1+g2) / L is set to 0.2-1.

2. The crankshaft of claim 1, wherein: The first micro groove (21) and the second micro groove (22) form a groove dam (24).

3. The crankshaft of claim 1, wherein: The first micro groove (21) extends away from the second micro groove (22) from one side thereof to the other side thereof in a direction away from the rotation direction of the crankshaft.

4. The crankshaft of claim 1, wherein: The included angle between the extension direction of the first micro groove (21) and the axial direction of the crankshaft is 10-80°.

5. The crankshaft of claim 1, wherein: The depth of the oil supply micro groove (20) is 2-50 μm.

6. The crankshaft of claim 1, wherein: The linear shape of the first micro groove (21) or / and the second micro groove (22) comprises a straight line or a curve.

7. The crankshaft of claim 1, wherein: The multiple oil supply micro grooves (20) distributed in the circumferential direction of the crankshaft constitute a micro groove group, and multiple micro groove groups are arranged in the axial direction of the crankshaft.

8. A rolling piston compressor comprising a crankshaft, characterized by: The crankshaft is according to any one of claims 1-7.

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