Dual-acting hydrodynamic axial slide bearing

Abstract

The present invention relates to a double-acting hydrodynamic axial sliding bearing (1), comprising a bearing housing (2) having: a first support body (3) disposed in the bearing housing having a first axial support surface (4); a second support body (5) disposed in the bearing housing having a second axial support surface (6); and a shaft (7) comprising at least one thrust disc (8), wherein the at least one thrust disc is disposed in the bearing housing between the first axial support surface and the second axial support surface and is capable of being supported on the first axial support surface or the second axial support surface depending on the axial position of the shaft, and forming a first or (9) or second annular chamber (12) depending on whether the thrust disc is supported on the first axial support surface or the second axial support surface.

Description

Technical Field

[0001] The present invention relates to a double-acting hydrodynamic axial sliding bearing as described in the preamble of independent claim 1. Background Technology

[0002] Double-acting hydrodynamic axial sliding bearings are widely used and are used to support shafts that bear axial loads.

[0003] A general-purpose double-acting hydrodynamic axial sliding bearing includes a bearing housing and a shaft with a thrust disc. Axial support surfaces are provided at each axial end of the bearing housing, and the thrust disc of the shaft to be supported can be rested on the axial support surfaces. Although the thrust disc is mentioned below as resting against the support surface, in a hydrodynamic bearing, there is never direct contact between the thrust disc and the corresponding support surface; a lubricating oil film is always present between the thrust disc and the bearing housing. Bearing oil is typically used as the lubricating medium.

[0004] When the thrust disk rests against one of the support surfaces, it forms an annular chamber that is closed relative to the rest of the bearing housing. This annular chamber is defined radially by the outer diameter of the shaft and the inner diameter of the support body, and axially by an axial wall (e.g., the wall of the bearing housing) and the side of the thrust disk facing the axial support surface.

[0005] Lubricating oil and / or air may accumulate in the annular chamber. When a multiphase filling state (air and oil) exists in the "chamber," a delay occurs between the force and reaction force acting on the axial bearing due to the compressibility of air. This delay can lead to instability in the shaft-bearing system, characterized by a pressure difference between the two chambers. This multiphase state can occur during operation, i.e., when the supplied oil quantity is insufficient to keep the chamber completely filled with oil at all times. Due to the pressure difference between the annular chamber and the remaining space, an axial force is applied to the shaft, causing it to move axially toward the previously unattached shoulder side. This creates a gap in the previously attached annular chamber, which favors the presence of an air fraction in that chamber during the next vibration cycle, since the oil supplied to the bearing is typically insufficient to completely fill the lubrication gap on the unattached side. When the shaft subsequently returns from the initially unattached side to the initially attached side, the air present there must first be purged. If purging is not rapid enough, the aforementioned instability and the resulting axial force may occur. The alternating axial forces induce axial vibrations in the shaft system, which can be further amplified by the axial natural frequencies that may exist in the shaft system. The resulting axial vibrations may lead to damage or failure of the axial bearings.

[0006] In addition to axial sliding bearings with a single thrust disc, axial sliding bearings with two thrust discs are also known, in which the aforementioned instabilities also occur. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide a double-acting hydrodynamic axial sliding bearing in which axial vibration excitation is avoided or at least significantly reduced.

[0008] The above objective is achieved by the features of independent claim 1.

[0009] Other further configurations of the invention, which may be implemented individually or in combination, constitute the subject matter of the dependent claims.

[0010] The double-acting hydrodynamic axial sliding bearing according to the present invention includes a bearing housing having: a first support body disposed in the bearing housing with a first axial support surface; a second support body disposed in the bearing housing with a second axial support surface; and a shaft including at least one thrust disc, wherein the at least one thrust disc is disposed in the bearing housing between the first axial support surface and the second axial support surface, and is capable of being supported on the first axial support surface or the second axial support surface depending on the axial position of the shaft, and forming a first annular chamber depending on whether the thrust disc is supported on the first axial support surface or the second axial support surface, the first annular chamber being closed relative to the remainder of the bearing housing. The first annular chamber is defined radially by the outer diameter of the shaft and the inner diameter of the first support body, and axially by the first axial wall and the side of the thrust disk facing the first axial support surface; or a second annular chamber is formed, which is closed relative to the rest of the bearing housing, and is defined radially by the outer diameter of the shaft and the inner diameter of the second support body, and axially by the second axial wall and the side of the thrust disk facing the second axial support surface. The chamber is characterized by providing a pressure balancing device that can reduce or balance the pressure difference between the first or second annular chamber and the remaining space separated by the first or second annular chamber.

[0011] Due to the effect of pressure balance, the axial vibration caused by alternating axial forces is completely eliminated or at least effectively reduced, thus preventing bearing damage or even failure.

[0012] According to a first embodiment of the present invention, the pressure balancing device includes a first pressure balancing pipeline and a second pressure balancing pipeline. The first and second pressure balancing pipelines are arranged and constructed such that one end of the corresponding pressure balancing pipeline connects the formed first annular chamber or second annular chamber to the external environment according to the position of the thrust plate, while the other corresponding pressure balancing pipeline connects the remaining space separated by the first annular chamber or second annular chamber to the external environment.

[0013] In this case, pressure balance is not achieved directly between the two annular chambers, but rather separately between each space (chamber) and the external environment. This implementation method is particularly simple to implement, requires no major structural investment, and can be added retrofitted if necessary.

[0014] Another embodiment of the present invention specifies that the pressure balancing device includes a first pressure balancing pipeline and a second pressure balancing pipeline, the first pressure balancing pipeline and the second pressure balancing pipeline being arranged and constructed such that one end of the pressure balancing pipeline leads to a first annular chamber or a second annular chamber formed according to the position of the thrust plate, and the corresponding other ends of the pressure balancing pipeline are directly or via the pressure balancing chambers connected to each other.

[0015] Through directly or indirectly interconnected pipelines, pressure balance can be easily achieved between the corresponding annular chamber and the space separated by the annular chamber. This solution can also be added retrofitted if necessary. Another alternative embodiment of the invention is characterized in that the pressure balancing device includes a first pressure balancing pipeline and a second pressure balancing pipeline, which are arranged and constructed such that a first end of the pressure balancing pipeline leads to a first or second annular chamber formed according to the position of the thrust plate, while the other end of the pressure balancing pipeline leads to the space separated by the annular chamber.

[0016] Compared to the previous solution, this solution results in less bearing wear. Attached Figure Description

[0017] The advantages of the present invention are further illustrated below through examples.

[0018] The attached diagram shows: Figure 1 This is a first embodiment of the double-acting hydrodynamic axial sliding bearing according to the present invention, wherein pressure balance is achieved relative to the external environment; Figure 2 This is a second embodiment of the double-acting hydrodynamic axial sliding bearing according to the present invention, wherein pressure balance is achieved by means of a pressure balance chamber; Figure 3 This is a third embodiment of the double-acting hydrodynamic axial sliding bearing according to the present invention, wherein internal pressure balance is achieved by means of two separate pressure balancing pipelines; Figure 4 This is a fourth embodiment of the double-acting hydrodynamic axial sliding bearing according to the present invention, wherein it has two thrust discs.

[0019] The accompanying drawings illustrate the double-acting hydrodynamic axial sliding bearing according to the invention only in a schematic manner and not necessarily to scale. The drawings show essentially only the components necessary for the invention. Identical or functionally equivalent components are indicated by the same reference numerals in the drawings. The double-acting hydrodynamic axial sliding bearing shown is merely an embodiment of such bearings; other embodiments, different from these, exist on the market, and the invention is equally applicable to these embodiments, all of which are included within the scope of protection of this invention. Detailed Implementation

[0020] Figure 1 A first embodiment of a double-acting hydrodynamic axial sliding bearing 1 according to the present invention is shown. The axial sliding bearing 1 includes a bearing housing 2, which can also be constructed as a multi-part assembly for ease of installation. Supports 3 and 5 are provided on the axial walls 10 and 13 of the bearing housing 2, each support having an axial support surface 4 and 6, on which a correspondingly constructed shoulder of the shaft 7 to be supported can rest. Depending on the axial (end) position of the shaft 7 or the thrust disc 8, a first annular chamber 9 is formed, which is closed relative to the rest of the bearing housing 2. The first annular chamber extends radially from the outer diameter D of the shaft 7. W and the inner diameter d of the first support 3 K The boundary is defined, and is defined axially by the first axial wall 10 and the side 11 of the thrust disk 8 facing the first axial support surface 4; or a second annular chamber 12 is formed, which is closed relative to the rest of the bearing housing 2, and is defined radially by the outer diameter D of the shaft 7. W The inner diameter d of the second support 5 K The boundary is defined by the second axial wall 13 and the side 14 of the thrust disk 8 facing the second axial support surface 6 in the axial direction.

[0021] Figure 1 The image shows the position where the thrust disk is at the first end and the first annular chamber 9 has been formed.

[0022] In this location, lubricating oil and air are present in the first annular chamber 9. Due to the multiphase filling state (air and oil) in the annular chamber 9, the compressibility of air causes a delay between the force and reaction force acting on the axial bearing. This delay may lead to instability in the shaft-bearing system, characterized by a pressure difference between the annular chamber 9 and the remaining space 15 separated by the first annular chamber 9. To balance this pressure difference, a pressure balancing device is provided. The pressure balancing device includes a first pressure balancing conduit and a second pressure balancing conduit 16, 17, which are arranged and constructed such that the first end of the corresponding pressure balancing conduit 16, 17 connects the formed first annular chamber or second annular chamber 9, 12 to the external environment according to the position of the thrust plate 8, while the other pressure balancing conduit 16, 17 connects the remaining space 15 separated by the first annular chamber or second annular chamber 9, 12 to the external environment. This achieves maximum pressure balance between space 9 or 12, which is largely separated by the thrust plate, and space 15, thereby avoiding or at least significantly reducing instability of the shaft-bearing system. Pressure balancing lines 16 and 17 can be formed by drilling simple holes in the bearing housing 2.

[0023] Figure 2 A second embodiment of the double-acting hydrodynamic axial sliding bearing 1 according to the present invention is shown. Its basic structure is similar to... Figure 1 The axial sliding bearing described herein is the same, therefore a more detailed description is cited herein. The main difference from the first embodiment is that, in Figure 2 In the illustrated embodiment, pressure balancing pipes 16 and 17 are directly connected to each other. One end of pressure balancing pipes 16 and 17 leads to the first or second annular chamber 9 or 12 formed according to the position of the thrust plate 8, while the other end of pressure balancing pipes 16 and 17 is directly connected to each other, or as shown in this embodiment, via pressure balancing chamber 18. In both embodiments, regardless of whether a balancing chamber is provided, effective pressure balance can be achieved between the first or second annular chamber 9 or 12 and the space 15 separated by the first or second annular chamber 9 or 12, thereby effectively preventing axial vibration of the shaft 13. The pressure balancing chamber 18 is optional and can dampen the pressure impact of the multiphase fluid in the pressure balancing pipes 16 and 17.

[0024] Figure 3 A third embodiment of the double-acting hydrodynamic axial sliding bearing 1 according to the present invention is shown. This embodiment is largely similar to... Figure 2 The structure of the central axial sliding bearing 1 is the same, and its detailed description is quoted here. (Similar to...) Figure 2Unlike the illustrated embodiment, the pressure balancing lines 16 and 17 are not directly or via the pressure balancing chambers. Instead, the pressure balancing lines 16 and 17 are arranged such that the first end of each line leads to a first annular chamber or a second annular chamber 9 or 12 formed according to the position of the thrust plate 8, while the other end of each line independently leads to a space 15 separated by the first annular chamber or the second annular chamber 9 or 12.

[0025] therefore, Figure 3 The embodiment shown also achieves effective pressure balance between the annular chambers 6 and 8, thereby preventing axial vibration of the shaft 13, which could otherwise cause damage or even destruction of the bearing.

[0026] Figure 4 A fourth embodiment of the double-acting hydrodynamic axial sliding bearing 1 according to the present invention is shown. In this example, the bearing is a bearing with two thrust discs 8 and 8a, and annular chambers 9 and 12 are formed by the outer diameter D of the shaft. W The inner diameter d of the axial bearing K The thrust plate consists of inner surfaces 11 and 14, and outer surfaces 10 and 13 of the bearing housing 2 located therebetween. In a combined axial-radial sliding bearing, the bearing housing 2 located therebetween may contain a radial sliding bearing and may be constructed as a separate component. In this example, pressure balancing can be achieved through pressure balancing conduits 16 and 17 provided in the bearing housing. Pressure balancing conduits described within the scope of this invention are, by definition, not limited to drilled or other forms of closed channels, but also include open channels, such as channels / grooves milled into the bearing housing. In principle, all of the aforementioned pressure balancing measures can also be retrofitted to existing bearings. The investment required for this and the costs incurred from such retrofitting are relatively limited, while preventing axial vibration of the shaft, thereby ensuring the safe operation of the bearing.

Claims

1. A double-acting hydrodynamic axial sliding bearing (1), comprising a bearing housing (2) having: a first support body (3) disposed in the bearing housing (2) having a first axial support surface (4); a second support body (5) disposed in the bearing housing (2) having a second axial support surface (6); and a shaft (7) comprising at least one thrust disc (8), wherein, The at least one thrust plate (8) is arranged in the bearing housing (2) between the first axial support surface (4) and the second axial support surface (6), and is capable of being supported on the first axial support surface (4) or the second axial support surface (6) according to the axial position of the shaft (7), and depending on whether the thrust plate (8) is supported on the first axial support surface (4) or the second axial support surface (6), - A first annular chamber (9) is formed, which is closed relative to the rest of the bearing housing (2), and the first annular chamber is formed radially by the outer diameter (D) of the shaft (7). W ) and the inner diameter (d) of the first support (3) K The boundary is defined by the first axial wall (10) and the side (11) of the thrust disk (8) facing the first axial support surface (4) in the axial direction; or - A second annular chamber (12) is formed, which is closed relative to the rest of the bearing housing (2), and the second annular chamber is formed radially by the outer diameter (D) of the shaft (7). W ) and the inner diameter (d) of the second support (5) K The boundary is defined by the second axial wall (13) and the side (14) of the thrust disk (8) facing the second axial support surface (6) in the axial direction. Its features are, A pressure balancing device is provided, which can reduce or balance the pressure difference between the first annular chamber (9) or the second annular chamber (12) and the remaining space (15) separated by the first annular chamber (9) or the second annular chamber (12).

2. The double-acting hydrodynamic axial sliding bearing (1) according to claim 1, characterized in that, The pressure balancing device includes a first pressure balancing pipeline (16) and a second pressure balancing pipeline (17). The first pressure balancing pipeline and the second pressure balancing pipeline are arranged and constructed such that one end of the corresponding pressure balancing pipeline (16, 17) is connected to the external environment through a first annular chamber (9) or a second annular chamber (12) formed according to the position of the thrust plate (8), while the other corresponding pressure balancing pipeline (16, 17) is connected to the external environment through the remaining space (15) separated by the first annular chamber (9) or the second annular chamber (12).

3. The double-acting hydrodynamic axial sliding bearing (1) according to claim 1, characterized in that, The pressure balancing device includes a first pressure balancing line (16) and a second pressure balancing line (17), which are arranged and constructed such that one end of the pressure balancing line (16, 17) leads to the first annular chamber (9) or the second annular chamber (12) formed according to the position of the thrust plate (8), while the corresponding other ends of the pressure balancing line (16, 17) are directly or via the pressure balancing chamber (18) connected to each other.

4. The double-acting hydrodynamic axial sliding bearing (1) according to claim 1, characterized in that, The pressure balancing device includes a first pressure balancing line (16) and a second pressure balancing line (17), which are arranged and constructed such that a first end of the pressure balancing line (16, 17) leads to a first annular chamber (9) or a second annular chamber (12) formed according to the position of the thrust plate (8), and the corresponding other end of the pressure balancing line (16, 17) leads to a space (15) separated by the first annular chamber (9) or the second annular chamber (12).

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