Hydrodynamic radial bearing

Abstract

The utility model discloses a hydrodynamic radial bearing, and relates to the technical field of bearing structure design. Comprising a bearing body and a shaft sleeve, a pre-gap is reserved between the bearing body and the shaft sleeve, and conical table boards are arranged at the two ends of the bearing body; a pressurizing blade is fixedly connected to the conical table board; in the axis direction of the bearing body, the thicknesses of the pressurizing blades are gradually increased in the extending direction from the end of the bearing body to the middle of the bearing body, and the distance between every two adjacent pressurizing blades is gradually reduced. The defects that in the prior art, a hydrodynamic radial bearing is limited in bearing capacity and poor in flow guiding effect are overcome. According to the hydrodynamic radial bearing, the amount of liquid entering the pre-clearance is increased and the supporting effect on the shaft sleeve is improved through the flow guide effect of the conical table board and the pressurizing blades; furthermore, through the reasonable design of the structure of the pressurizing blade, the flowing stability of the liquid is ensured, the possibility of turbulent flow is reduced, and the supporting stability of the shaft sleeve is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of bearing structure design, in particular to a hydrodynamic radial bearing. Background Technique

[0002] Centrifugal pumps have the characteristics of long working life, flat head curves, strong conveying capacity, etc., and are now widely used in industries such as aerospace, petrochemical, chemical fertilizer and pharmaceutical industries.

[0003] Most centrifugal pumps use rolling bearings or sliding bearings as the support bearings for the rotating shaft. However, rolling bearings or sliding bearings usually have the following defects: for example, failure due to continuous wear of the metal on the working surface, and there are problems such as lubricant aging and high-temperature dilution when using lubricants to lubricate the bearings.

[0004] Therefore, a new type of hydrodynamic bearing has begun to be used in centrifugal pumps. A hydrodynamic bearing is a non-contact sliding bearing that uses viscous liquid as a lubricant. The hydrodynamic bearing uses the liquid film pressure formed by the liquid in the bearing wedge gap during the rotation of the rotating shaft to support the load. Compared with rolling bearings and sliding bearings, hydrodynamic bearings have the advantages of smooth rotation, reliable operation, low noise, small vibration, small volume, and light weight. The hydrodynamic bearing uses the system working medium as a lubricant, so there is no need to consider the pollution of the lubricant to the system. Moreover, on the premise of fully ensuring the lubrication of the system working medium, the working surfaces of the bearings are separated by the system working medium and do not come into direct contact, which can greatly reduce surface wear.

[0005] Cavitation is likely to occur when the hydrodynamic bearing rotates at high speed. "Cavitation" refers to the phenomenon that the local pressure in the liquid medium is lower than the saturation pressure corresponding to the liquid temperature, resulting in the vaporization of the liquid. When the rotating shaft rotates, a high-pressure area and a low-pressure area will be formed in the cavity between the rotating shaft and the hydrodynamic bearing. And as the rotational speed of the rotating shaft gradually increases, the pressure in the low-pressure area decreases correspondingly. When the liquid pressure in the low-pressure area in the cavity between the rotating shaft and the hydrodynamic bearing is lower than the saturation pressure corresponding to the incoming liquid, cavitation will occur in the cavity.

[0006] Due to the very small lubrication gap between the rotating shaft and the hydrodynamic bearing, the heat generated during the rotation of the rotating shaft also increases the temperature of the liquid film in the low-pressure area, and the corresponding liquid film saturation pressure value also rises accordingly, increasing the possibility of cavitation. When cavitation occurs in the liquid, part of the liquid changes into gas. Since the specific volume of the gas is much larger than that of the liquid, the gas quickly occupies most of the volume in the cavity, and the liquid film support force drops rapidly or even disappears, thus affecting the stability of the hydrodynamic bearing at high speeds and even causing failure in severe cases.

[0007] In the existing invention patent, the application number is: 201910095029.5, and the patent name is: A hydrodynamic radial bearing and a centrifugal pump; there are still the following defects:

[0008] 1. The blade structure design is unreasonable, and the guiding effect on the liquid is not good;

[0009] 2. Turbulence is likely to occur in the flow of the liquid during the drainage process, reducing the carrying stability of the entire bearing.

[0010] It can be seen that in the prior art, the hydrodynamic radial bearing has the defects of limited load-bearing capacity and poor guiding effect. Utility Model Content

[0011] In view of this, the main purpose of the present utility model is to provide a hydrodynamic radial bearing that improves the supporting effect on the shaft sleeve, ensures the smoothness of liquid flow, reduces the possibility of turbulence, and ensures the stability of the support for the shaft sleeve.

[0012] To achieve the above object, the technical solution of the present utility model is realized as follows:

[0013] A hydrodynamic radial bearing includes: a bearing body and a shaft sleeve. A pre-clearance is provided between the bearing body and the shaft sleeve, and tapered table surfaces are provided at both ends of the bearing body;

[0014] In a preferred embodiment, booster blades are fixedly connected to the tapered table surfaces;

[0015] In a preferred embodiment, in the axial direction of the bearing body, the thickness of the booster blades gradually increases from the end of the bearing body towards the middle, and the distance between adjacent booster blades gradually decreases.

[0016] In a preferred embodiment, both sides of the booster blade are respectively: a flow-facing side and a back-flow side. In the axial direction of the bearing body, the flow-facing side is an arc surface, and the back-flow side is a straight surface.

[0017] In a preferred embodiment, the booster blades are integrally inclined, and the inclination direction of the booster blades is the same as the rotation direction of the bearing body.

[0018] In a preferred embodiment, the upper side of the booster blade away from the tapered table surface is an arc surface.

[0019] In a preferred embodiment, the cross-sectional dimensions of the booster blade gradually decrease and smoothly transition from the tapered table surface to the upper arc surface.

[0020] In a preferred embodiment, the upper side of the booster blade away from the tapered table surface is flush with the outer wall of the bearing body.

[0021] In a preferred embodiment, the booster vanes on both end faces of the bearing body are symmetrically arranged.

[0022] In a preferred embodiment, the booster vanes are evenly arranged.

[0023] In a preferred embodiment, it further includes: a booster groove, which is opened at both ends of the outer wall of the bearing body near the conical table surface.

[0024] In a preferred embodiment, the booster groove is opened in the extending direction of the gap between adjacent booster vanes;

[0025] In a preferred embodiment, in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the width of the booster groove gradually decreases;

[0026] In a preferred embodiment, in the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the booster groove bends away from the rotation direction of the bearing body;

[0027] In a preferred embodiment, a wedge-shaped cavity is opened on the entire circumference of the end of the outer wall of the bearing body.

[0028] In a preferred embodiment, a diversion groove is opened inside the wedge-shaped cavity, and one end of the diversion groove is conducted outside the bending arc of the booster groove;

[0029] In a preferred embodiment, a plurality of diversion grooves are opened;

[0030] In a preferred embodiment, one end of each diversion groove away from the booster groove is located at one end of the wedge-shaped cavity close to the middle of the bearing body;

[0031] In a preferred embodiment, one end of each diversion groove away from the booster groove is located on the same circumferential line of the bearing body.

[0032] The hydrodynamic radial bearing of the present invention has the following beneficial effects:

[0033] This hydrodynamic radial bearing includes: a bearing body and a bushing. A pre-clearance is left between the bearing body and the bushing. Conical table surfaces are opened at both ends of the bearing body; Booster vanes are fixedly connected to the conical table surfaces; In the axial direction of the bearing body, in the extending direction from the end of the bearing body to the middle, the thickness of the booster vanes gradually increases, and the distance between adjacent booster vanes gradually decreases.

[0034] It solves the defects that the hydrodynamic radial bearing in the prior art has limited load-bearing capacity and poor diversion effect.

[0035] The hydrodynamic radial bearing improves the amount of liquid entering the pre-clearance and the supporting effect on the bushing through the guiding action of the conical table surface and the booster vanes; further, through the reasonable design of the structure of the booster vanes, the smoothness of liquid flow is ensured, the possibility of turbulent flow is reduced, and the stability of the support for the bushing is ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 FIG. is a schematic structural diagram of a hydrodynamic radial bearing according to an embodiment of the present disclosure;

[0038] Figure 2 FIG. is a side view of a hydrodynamic radial bearing according to an embodiment of the present disclosure;

[0039] Figure 3 FIG. is a schematic structural diagram of the bearing body of a hydrodynamic radial bearing according to an embodiment of the present disclosure.

[0040]

SYMBOLS OF MAIN COMPONENTS

[0041] 1. Bearing body; 2. Bushing; 3. Conical table surface;

[0042] 4. Booster vane;

[0043] 41. Flow-facing side; 42. Flow-back side;

[0044] 5. Booster groove;

[0045] 6. Flow guiding groove. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] The following further details the hydrodynamic radial bearing of the present invention in conjunction with the drawings and the embodiments of the present invention.

[0047] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0049] It should be noted that the terms "first", "second", etc. in the description and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that comprises a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0050] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "above", etc. can be used herein to describe the spatial positional relationship of a device or feature shown in the figure with other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the figure. For example, if the device in the figure is inverted, the device described as "above" or "over" other devices or structures will then be positioned "below" or "beneath" other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the corresponding explanations are made for the spatial relative descriptions used herein.

[0051] As Figures 1 - 3 shown, the hydrodynamic radial bearing includes: a bearing body 1 and a bushing 2. A pre-clearance is provided between the bearing body 1 and the bushing 2, and tapered table surfaces 3 are provided at both ends of the bearing body 1;

[0052] In order to increase the pressure of the hydrodynamic oil film, a booster vane 4 is fixedly connected to the tapered table surface 3; the guiding liquid enters the interior of the pre-clearance.

[0053] To improve the diversion effect on the liquid, the liquid is compressed at the boosting vane 4 to increase the pressure of the liquid entering the pre-gap and enhance the load-bearing capacity of the hydrodynamic oil film. In the axial direction of the bearing body 1, the thickness of the boosting vane 4 gradually increases from the end of the bearing body 1 towards the middle, and the distance between adjacent boosting vanes 4 gradually decreases.

[0054] During the long-term use, as the liquid pressure increases during the extension of the boosting vane 4 from the end to the middle of the bearing body 1, the load-bearing capacity of the boosting vane needs to gradually increase. In the prior art, the thicknesses of the boosting vanes 4 are the same. During long-term use, the boosting vanes near the middle of the bearing body 1 are prone to damage, seriously affecting the service life of the entire product. By increasing the thickness of the boosting vane 4, it is ensured that during the gradual entry of the liquid into the pre-gap, the pressure-bearing capacity of the boosting vane is guaranteed, the service life of the boosting vane is ensured, and the defect of damage to the boosting vane during long-term use is avoided.

[0055] To improve the diversion effect, ensure that the liquid does not show turbulence, and gradually increase the pressure of the liquid to ensure the effect of the hydrodynamic oil film. The two sides of the boosting vane 4 are respectively: the upstream side 41 in front of the rotation of the bearing body 1 and the downstream side 42 behind the rotation of the bearing body 1. In the axial direction of the bearing body 1, the upstream side 41 is an arc surface, which has a better diversion effect. The downstream side 42 is a straight surface, which stabilizes the flow direction of the liquid and reduces the possibility of turbulence. In the axial direction, one side is an arc and the other side is a straight surface, and the overall thickness increases uniformly. Moreover, the distance between adjacent boosting vanes 4 gradually decreases to improve the boosting effect on the liquid. Ensure that during the process of the liquid entering the reserved gap, the volume gradually and uniformly decreases and the pressure gradually increases, ensuring the stability of boosting and improving the boosting effect.

[0056] To improve the boosting effect of the entire boosting vane 4, reduce the effect of the liquid on the bushing 2 when initially entering the bearing body 1, ensure a larger supporting effect on the bushing 2 after the liquid boosting is stable, and improve the stability of the support for the bushing 2. The boosting vane 4 is integrally inclined, and the inclination direction of the boosting vane 4 is the same as the rotation direction of the bearing body 1. That is: the upper end of the boosting vane 4 inclines towards the upstream side 41. During the initial action of the boosting vane 4 on the liquid, it mainly drives the liquid to flow towards the middle of the bearing body 1 through the boosting vane 4, reducing the effect of the liquid on the bushing 2.

[0057] To improve the smoothing effect and ensure that the liquid overflows smoothly. The upper side of the boosting vane 4 away from the conical table 3 is an arc surface.

[0058] In order to improve the pressure-bearing effect of the booster vane 4, at one end of the booster vane 4 close to the bushing 2, the pressure-bearing is relatively small, and there can be a large-space drainage effect. The cross-sectional dimension of the booster vane 4 gradually decreases and smoothly transitions from the conical table surface 3 to the upper arc surface. By increasing the opening size of the booster vane 4 at the end of the bearing body 1, the flow rate of the liquid entering the bearing body 1 can be maximized. Also, the pressure-bearing strength of the booster vane 4 can be ensured, and the boosting effect of the booster vane 4 can be improved.

[0059] In order to maximize the drainage, reduce the overflow of the liquid, and ensure the boosting effect. The upper side of the booster vane 4 far from the conical table surface 3 is flush with the outer wall of the bearing body 1. To a certain extent, the supporting effect on the bushing 2 is also improved, ensuring the supporting stability of the bushing.

[0060] Of course, in order to provide a balanced supporting effect on both ends of the bushing 2 and improve the stability of the bushing 2. The booster vanes 4 on both end faces of the bearing body 1 are symmetrically arranged.

[0061] In order to enable the bearing body 1 to rotate smoothly during self-rotation. The booster vanes 4 are evenly arranged.

[0062] In order to further improve the boosting effect and ensure smooth flow of the liquid during the entry into the pre-clearance. It further includes: a boosting groove 5, which is opened at both ends of the outer wall of the bearing body 1 close to the conical table surface 3. Through the re-diversion and boosting of the boosting groove 5, it is ensured that the pressure of the liquid entering the pre-clearance is close to the pressure of the liquid in the reserved clearance, and the excess liquid can overflow smoothly.

[0063] In order to cooperate with the booster vane 4 for diversion, ensure the smooth flow of the liquid, improve the diversion effect, and thus increase the boosting effect of the liquid. The boosting groove 5 is opened in the extending direction of the gap between adjacent booster vanes 4.

[0064] In order to increase the pressure of the hydrodynamic oil film, boosting grooves 5 are opened on the outer walls at both ends of the bearing body 1; through the diversion of the boosting grooves 5 into the pre-clearance, the flow rate of the liquid entering the pre-clearance is increased, the boosting effect is improved, and the supporting stability effect on the bushing 2 is ensured.

[0065] In order to ensure the centrifugal effect on the liquid during the liquid diversion process, increase the pressure on the liquid, ensure the pressure-bearing capacity of the liquid, and improve the supporting effect on the bushing. In the axial direction of the bearing body 1, in the extending direction from the end of the bearing body 1 to the middle, the width of the boosting groove 5 gradually decreases; the depth of the boosting groove 5 also gradually decreases, and even the bottom of the boosting groove 5 smoothly transitions to the surface of the bearing body 1.

[0066] In order to improve the effect of adapting to the centrifugal action and ensure a better pressurizing effect on the liquid during the centrifugal operation. In the axial direction of the bearing body 1, in the extending direction from the end of the bearing body 1 towards the middle, the pressurizing groove 5 bends away from the rotating direction of the bearing body 1.

[0067] In order to increase the amount of liquid entering between the bearing body 1 and the bushing 2 in the initial stage and improve the supporting effect on the bushing. A wedge-shaped cavity is provided on the entire circumference of the outer wall end of the bearing body 1. Through the guiding action of the wedge-shaped cavity, the amount of entering liquid is increased to ensure the supporting effect. There is a smooth transition between the wedge-shaped cavity and the conical table surface 3.

[0068] In order to enable the liquid in the diversion groove 6 to flow smoothly into the pre-clearance and improve the smooth entry of the liquid into the pre-clearance. A diversion groove 6 is provided inside the wedge-shaped cavity, and one end of the diversion groove 6 is conducted on the outer side of the bending arc of the pressurizing groove 5.

[0069] In order to improve the drainage effect, a plurality of the diversion grooves 6 are provided.

[0070] In order to improve the diversion effect and ensure the smooth diversion of the liquid towards the middle of the bearing body 1. One end of each diversion groove 6 away from the pressurizing groove 5 is located at one end of the wedge-shaped cavity close to the middle of the bearing body 1.

[0071] In order to ensure the bearing capacity of the bearing body 1 and ensure that a pre-clearance can be smoothly formed in the part of the bearing body 1 other than the wedge-shaped cavity to ensure the hydrodynamic oil film bearing capacity of the liquid. One end of each diversion groove away from the pressurizing groove is located on the same circumferential line of the bearing body 1.

[0072] The above is only the preferred embodiment of the present invention and is not used to limit the protection scope of the present invention.

Claims

1. A hydrodynamic radial bearing, characterized in that, Comprising: A bearing body (1) and a bushing (2), a pre-clearance is provided between the bearing body (1) and the bushing (2), and tapered table surfaces (3) are provided at both ends of the bearing body (1); A pressure-boosting blade (4) is fixedly connected to the tapered table surface (3); In the axial direction of the bearing body (1), in the direction from the end of the bearing body (1) to the middle, the thickness of the pressure-boosting blade (4) gradually increases, and the distance between adjacent pressure-boosting blades (4) gradually decreases.

2. The hydrodynamic journal bearing according to claim 1, characterized in that, Both sides of the pressure-boosting blade (4) are respectively: a flow-facing side (41) and a flow-back side (42). In the axial direction of the bearing body (1), the flow-facing side (41) is an arc surface, and the flow-back side (42) is a straight surface.

3. The hydrodynamic radial bearing according to claim 1, characterized in that, The pressure-boosting blade (4) is integrally inclined, and the inclination direction of the pressure-boosting blade (4) is the same as the rotation direction of the bearing body (1).

4. The hydrodynamic radial bearing according to claim 1, characterized in that, The upper side of the pressure-boosting blade (4) away from the tapered table surface (3) is an arc surface.

5. The hydrodynamic radial bearing according to claim 4, characterized in that, The cross-sectional dimension of the pressure-boosting blade (4) gradually shrinks and smoothly transitions from the tapered table surface (3) to the upper arc surface.

6. The hydrodynamic radial bearing according to claim 1, characterized in that, The upper side of the pressure-boosting blade (4) away from the tapered table surface (3) is flush with the outer wall of the bearing body (1).

7. The hydrodynamic radial bearing according to any one of claims 1-6, characterized in that, The pressure-boosting blades (4) at both end faces of the bearing body (1) are symmetrically arranged.

8. The hydrodynamic radial bearing according to any one of claims 1-6, characterized in that, The pressure-boosting blades (4) are evenly arranged.

9. The hydrodynamic radial bearing according to claim 8, wherein Also comprising: A pressure-boosting groove (5), the pressure-boosting groove (5) is provided at both ends of the outer wall of the bearing body (1) near the tapered table surface (3).

10. The hydrodynamic radial bearing according to claim 9, characterized in that, The pressure-boosting groove (5) is provided in the extending direction of the gap between adjacent pressure-boosting blades (4); In the axial direction of the bearing body (1), in the direction from the end of the bearing body (1) to the middle, the width of the pressure-boosting groove (5) gradually shrinks; In the axial direction of the bearing body (1), in the direction from the end of the bearing body (1) to the middle, the pressure-boosting groove (5) bends away from the rotation direction of the bearing body (1); A wedge-shaped cavity is provided in the entire circumference of the outer wall end of the bearing body (1); A diversion groove (6) is provided inside the wedge-shaped cavity, and one end of the diversion groove (6) is conducted outside the bending arc of the pressure-boosting groove (5); A plurality of the diversion grooves (6) are provided; One end of each diversion groove (6) away from the pressure-boosting groove (5) is located at one end of the wedge-shaped cavity close to the middle of the bearing body (1); One end of each diversion groove (6) away from the pressure-boosting groove (5) is located on the same circumference of the bearing body (1).

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