Self-adaptive hydrostatic bearing

Abstract

The invention discloses a self-adaptive hydrostatic bearing, belongs to the technical field of hydrostatic bearings, and is used for providing active small-range two-dimensional rotary motion when a track surface of a guide rail or a rotary table is slightly inclined and has surface shape change. The adjusting ball supporting seat is characterized in that a concave conical supporting surface is arranged on the adjusting ball supporting seat and is in linear contact with the adjusting ball, a four-oil-cavity structure is adopted, and an oil inlet of each oil cavity is provided with a detachable self-feedback throttler. During working, hydraulic oil enters the oil cavity through the self-feedback throttler to form a bearing oil film. The self-feedback throttler can adjust the flow in a self-adaptive mode according to the pressure change of the oil cavity, and the matching structure of the inwards-concave conical supporting face and the adjusting ball allows the oil pad assembly to conduct small-range two-dimensional rotation motion. Under the synergistic effect, when the track surface slightly inclines, the pressure distribution of all the oil cavities is dynamically adjusted, posture compensation is achieved, the surface shape change of the track surface is adapted, it is ensured that a stable oil film gap is formed between bearing surfaces, and finally the high bearing capacity and the high supporting rigidity are obtained.

Description

Technical Field

[0001] This invention belongs to the field of hydrostatic bearing technology, and specifically relates to an adaptive hydrostatic bearing. Background Technology

[0002] Hydrostatic bearings are widely used in high-precision, heavy-duty mechanical equipment, such as large precision machine tools, heavy-duty rotary tables, and machine tool guideways, due to their high load-bearing capacity, excellent damping characteristics, and near-zero friction operation. Their core principle is to introduce pressurized oil into the oil cavity between the bearing and the moving parts (guideway or rotary table track surface) through an external oil supply system, forming a load-bearing oil film and achieving contactless support.

[0003] Traditional stationary hydrostatic bearings typically have a rigidly mounted bearing body. This structure has significant drawbacks in actual operating conditions: when the thrust surface tilts slightly due to thermal deformation, load bias, or installation errors, the rigidly mounted bearing cannot actively adjust its posture, resulting in thinning of the oil film clearance on the tilted side (even to the point of metal-to-metal contact) and increased clearance on the opposite side. This directly leads to decreased oil film stiffness, localized temperature rise, and accelerated wear, and in severe cases, oil film rupture and failure. Large guideways or turntables often have localized surface shape errors on their thrust surfaces. The rigid oil pads of traditional stationary hydrostatic bearings cannot conform to these non-ideal planes, resulting in excessively thin or missing oil films in certain areas, significantly reducing load uniformity and system lifespan.

[0004] Therefore, there is an urgent need in the existing technology for a new type of adaptive hydrostatic bearing with a relatively simple and reliable structure that can actively perform small-range two-dimensional rotational motion to accurately compensate for the tilt and local surface shape changes of the track surface in any direction, ensuring that the oil pad surface always maintains the best contact with the track surface. Thus, under the synergistic effect of each oil cavity, a uniform and stable oil film gap distribution is maintained, ensuring that the high load-bearing capacity and high support stiffness of the bearing oil film can be sustained under complex working conditions. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] An adaptive hydrostatic bearing includes a bearing housing, an oil gasket, an adjusting ball, a self-feedback throttle, and an adjusting ball support.

[0007] The adaptive hydrostatic bearing adopts a four-chamber structure, with a detachable self-feedback throttle at the oil inlet of each chamber. Simultaneously, the adjusting ball support is bolted to the upper surface of the bearing housing, and the upper surface of the adjusting ball support has a concave conical support surface that makes line contact with the adjusting ball. The self-feedback throttle adaptively adjusts the flow rate according to changes in oil chamber pressure. The mating structure between the concave conical support surface and the adjusting ball allows the oil pad to generate a small-range two-dimensional rotational motion when the track surface tilts slightly or changes in surface shape. The flow rate adjustment of the self-feedback throttle and the small-range two-dimensional rotational motion of the oil pad work together to achieve active attitude compensation of the oil pad when the track surface tilts slightly or changes in surface shape.

[0008] The center of the adjusting ball coincides with the rotation center of the oil pad, and the oil pad is connected to the limit roller by bolts.

[0009] The present invention has the following beneficial effects:

[0010] The purpose of this invention is to provide a novel adaptive hydrostatic bearing that can adjust its attitude and compensate for track surface tilt through a small range of two-dimensional rotational motion.

[0011] This invention, through the mating structure of an inwardly conical support surface and an adjusting ball, enables the oil pad assembly to perform a small-range two-dimensional rotational motion around its axis when the guide rail or turntable experiences slight tilting, and can adjust its posture to adapt to changes in the track surface shape. This structure works synergistically with the self-feedback throttle device's adaptive flow regulation based on pressure changes in each oil chamber. When the track surface exhibits tilting in any direction or local surface shape changes, this structure can adjust the oil pad's posture, making its working surface more closely conform to the tilted surface, optimizing the pressure distribution and oil film thickness in each oil chamber, effectively preventing localized thinning or breakage of the oil film, and ensuring the formation of a uniform, stable, and continuous high-rigidity oil film across the entire bearing surface. This fundamentally solves the core problem of traditional rigid bearings' inability to adapt to posture changes, leading to oil film failure. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the adaptive hydrostatic bearing of the present invention, wherein 1-bearing housing, 2-bearing limiting seat, 3-limiting roller, 4-oil pad, 5-adjusting ball, 6-fixed fixture, 7-self-feedback throttle, 8-oil return baffle, 9-oil inlet pipe joint, 10-adjusting ball support seat;

[0013] Figure 2 This is a top view schematic diagram of the adaptive hydrostatic bearing of the present invention;

[0014] Figure 3 This is an exploded view of the adaptive hydrostatic bearing of the present invention;

[0015] Figure 4This is a diagram showing the arrangement of the adaptive hydrostatic bearing of the present invention on a hydrostatic turntable. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0017] like Figure 1 As shown, the present invention provides an adaptive hydrostatic bearing, including a bearing housing 1, an oil pad 4, an adjusting ball 5, a self-feedback throttle 7, and an adjusting ball support 10.

[0018] The adaptive hydrostatic bearing adopts a four-chamber structure, with a detachable self-feedback throttle 7 configured at the oil inlet of each chamber. Simultaneously, the adjusting ball support 10 is bolted to the upper surface of the bearing housing 1, and the upper surface of the adjusting ball support 10 has a concave conical support surface that makes line contact with the adjusting ball 5. The self-feedback throttle 7 adaptively adjusts the flow rate according to changes in the oil chamber pressure. The mating structure between the concave conical support surface and the adjusting ball 5 allows the oil pad 4 to generate a small-range two-dimensional rotational motion when the track surface tilts slightly or changes in surface shape. The flow rate adjustment of the self-feedback throttle 7 and the small-range two-dimensional rotational motion of the oil pad 4 work together to achieve active attitude compensation for the oil pad 4 when the track surface tilts slightly or changes in surface shape.

[0019] The center of the adjusting ball 5 coincides with the rotation center of the oil pad 4, and the oil pad 4 is connected to the limiting roller 3 by bolts.

[0020] The adaptive hydrostatic bearings are arranged in any of the following ways: arranged at equal angular intervals around the central axis of the hydrostatic turntable; or arranged linearly at equal intervals along the direction of movement of the hydrostatic guide rail. When the hydrostatic turntable or the hydrostatic guide rail surface tilts or changes in shape, the adaptive hydrostatic bearing group maintains the continuity of the overall oil film through independent two-dimensional compensation and cooperation of each adaptive hydrostatic bearing.

[0021] The adaptive hydrostatic bearing also includes a bearing limit seat 2 and a limit roller 3. The bearing limit seat 2 is fixedly installed on the bearing seat 1, and the limit roller 3 is bolted to the oil pad 4. The central axis of the limit roller 3 coincides with the rotation center of the adjusting ball 5, thereby ensuring that the rotation center of the adjusting ball 5 coincides with the rotation center of the oil pad 4. This is used to constrain the rotation of the oil pad 4 about a direction perpendicular to the oil pad surface, while allowing the oil pad 4 to rotate two-dimensionally about two orthogonal directions within the oil pad surface on the oil pad 4 through the rotation center.

[0022] Hydraulic oil flows through the inlet pipe joint 9 to the self-feedback throttle 7 and then into the oil chamber of the oil pad 4, forming a high-rigidity oil film support between the surface of the oil pad 4 and the track surface. The oil pad 4 is equipped with a return oil baffle 8 to control the flow of oil to the return oil groove.

[0023] The adaptive hydrostatic bearing also includes a fixing fixture 6, which is fixed to the oil gasket 4 by screws and positioned by a cylindrical pin.

[0024] The principle of this invention is as follows: When the adaptive hydrostatic bearing is working, a hydraulic oil flows through the oil inlet pipe joint 9 to the self-feedback throttle 7. After throttling, it enters the oil cavity of the oil pad 4, so that a high-rigidity oil film support is formed between the oil pad surface and the track surface. The oil pad 4 is equipped with a return oil baffle 8 to control the flow of oil to the return oil groove.

[0025] When the oil chamber pressure changes during operation, the self-feedback throttle 7 adaptively adjusts the flow rate according to the pressure change. When the oil pad 4 tilts slightly or changes in its surface shape, the oil pad 4 generates a small-range two-dimensional rotational motion when the track surface tilts slightly or changes in its surface shape. The flow rate adjustment of the self-feedback throttle 7 and the small-range two-dimensional rotational motion work together to achieve attitude compensation.

[0026] like Figure 1 The diagram shown is a structural schematic of an adaptive hydrostatic bearing.

[0027] First, the design of the hydrostatic bearing incorporates a concave conical support surface and an adjusting ball to create a mating structure, enabling the oil pad assembly (including oil pad 4, self-feedback throttle 7, and return oil baffle 8) to perform a small-range two-dimensional rotation around its axis when the guide rail or turntable experiences slight tilting or local surface changes.

[0028] Secondly, the small-range two-dimensional rotation of the oil pad 4 around the axis and the adaptive flow regulation of the four self-feedback throttles based on the pressure changes in each oil chamber work synergistically. When the track surface is tilted in any direction or has local surface shape changes, the adaptive hydrostatic bearing of this invention can adjust the posture of the oil pad 4, making its working surface fit the tilted surface better, optimizing the pressure distribution and oil film thickness of each oil chamber, effectively avoiding local thinning or breakage of the oil film, and ensuring the formation of a uniform, stable, and continuous high-rigidity oil film on the entire track bearing surface;

[0029] Third, the hydraulic station outputs pressure oil, which flows to the self-feedback throttle 7 after passing through the oil inlet pipe joint 9. After throttling, it enters the oil chamber of the oil pad 4, forming a high-rigidity oil film support between the oil pad surface and the track surface. The oil pad 4 is equipped with a return oil baffle 8 to control the flow of oil to the return oil groove.

[0030] like Figure 1 , Figure 2, Figure 3 As shown, the adaptive hydrostatic bearing of the present invention includes: a bearing housing 1 is bolted to the upper surface of an external hydraulic turntable base, and an adjusting ball support 10 is bolted to the upper surface of the bearing housing 1; the adjusting ball support 10 is provided with a concave conical support surface, the adjusting ball 5 is disposed in the concave conical support surface of the adjusting ball support 10, and the concave conical support surface of the adjusting ball support 10 is in line contact with the adjusting ball 5, so that the oil pad 4 generates a small range of two-dimensional rotational motion when the track surface is slightly tilted or when the track surface has a surface shape change; the bearing limiting seat 2 is fixedly installed on the bearing housing 1, and the limiting roller 3 is bolted to the oil pad 4, and the central axis of the limiting roller 3 coincides with the rotation center of the adjusting ball 5, thereby ensuring that it coincides with the rotation center of the oil pad 4. During assembly (without installing the self-feedback throttle 7), first install the fixing fixture 6. Secure the fixing fixture 6 to the oil gasket 4 with screws and position it using cylindrical pins. After installing the adaptive hydrostatic bearing onto the turntable or hydrostatic guide rail, remove the fixing fixture 6 and install the feedback throttle 7 onto the oil gasket 4. Install the return oil baffle 8 onto the oil gasket 4 with screws and apply sealant to the connection to prevent oil leakage. Finally, install the oil inlet pipe connector 9 to the oil inlet of the oil gasket 4.

[0031] like Figure 4 The diagram shows the arrangement of adaptive hydrostatic bearings on a hydrostatic turntable. This invention requires the adaptive hydrostatic bearings to be arranged in the following manner: spaced at equal angular intervals around the central axis of the hydrostatic turntable; when the turntable track surface tilts, the bearing group maintains overall oil film continuity through independent two-dimensional compensation and coordination of each bearing.

[0032] The above description is merely an embodiment of the present invention and does not limit the scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related system fields, are similarly included within the protection scope of the present invention.

[0033] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. An adaptive hydrostatic bearing, characterized in that, Includes bearing housing, oil gasket, adjusting ball, self-feedback throttle, and adjusting ball support; The adaptive hydrostatic bearing adopts a four-chamber structure, and a detachable self-feedback throttle is configured at the oil inlet of each chamber. Simultaneously, the adjusting ball support is bolted to the upper surface of the bearing housing, and the upper surface of the adjusting ball support has a concave conical support surface that makes line contact with the adjusting ball. The self-feedback throttle adaptively adjusts the flow rate according to changes in the oil chamber pressure. The mating structure between the concave conical support surface and the adjusting ball allows the oil pad to generate a small-range two-dimensional rotational motion when the track surface tilts slightly or when there are changes in surface shape. The flow rate adjustment of the self-feedback throttle and the small-range two-dimensional rotational motion of the oil pad work together to achieve active attitude compensation of the oil pad when the track surface tilts slightly or when there are changes in surface shape. The center of the adjusting ball coincides with the rotation center of the oil pad, and the oil pad is connected to the limit roller by bolts.

2. The adaptive hydrostatic bearing according to claim 1, characterized in that, It also includes a bearing limit seat and a limit roller. The bearing limit seat is fixedly installed on the bearing seat, and the limit roller is bolted to the oil pad. The central axis of the limit roller coincides with the rotation center of the adjusting ball.

3. The adaptive hydrostatic bearing according to claim 1, characterized in that, After passing through the inlet pipe joint, the hydraulic oil flows to the self-feedback throttle and then enters the oil chamber of the oil pad, forming a high-rigidity oil film support between the oil pad surface and the track surface. The oil pad is equipped with a return oil baffle to control the flow of oil to the return oil groove.

4. The adaptive hydrostatic bearing according to claim 1, characterized in that, The adaptive hydrostatic bearings are arranged in the following manner: they are arranged at equal angular intervals around the central axis of the hydrostatic turntable; wherein, when the hydrostatic turntable or hydrostatic guide rail surface tilts or changes in shape, the adaptive hydrostatic bearing group maintains the continuity of the overall oil film through independent two-dimensional compensation and cooperation of each adaptive hydrostatic bearing.

5. The adaptive hydrostatic bearing according to claim 1, characterized in that, The adaptive hydrostatic bearings are arranged linearly at equal intervals along the direction of motion of the hydrostatic guide rail. When the hydrostatic turntable or the hydrostatic guide rail surface tilts or changes in shape, the adaptive hydrostatic bearing group maintains the continuity of the overall oil film through independent two-dimensional compensation and coordination of each adaptive hydrostatic bearing.

6. The adaptive hydrostatic bearing according to claim 1, characterized in that, When the adaptive hydrostatic bearing is working, one hydraulic oil flows through the inlet pipe joint to the self-feedback throttle. After throttling, it enters the oil chamber of the oil pad, forming a high-rigidity oil film support between the oil pad surface and the track surface. The oil pad is equipped with a return oil baffle to control the flow of oil to the return oil groove.

7. The adaptive hydrostatic bearing according to claim 1, characterized in that, When the oil chamber pressure changes during operation, the self-feedback throttle adaptively adjusts the flow rate according to the pressure change. When the oil pad tilts slightly or changes in its surface shape, a concave conical support surface on the adjusting ball support seat makes line contact with the adjusting ball. Therefore, when the oil pad tilts slightly or changes in its surface shape on the track surface, it generates a small-range two-dimensional rotational motion. The flow rate adjustment of the self-feedback throttle and the small-range two-dimensional rotational motion work together to achieve attitude compensation.

8. The adaptive hydrostatic bearing according to claim 1, characterized in that, The bearing housing is bolted to the upper surface of the external hydraulic turntable base.

9. The adaptive hydrostatic bearing according to claim 1, characterized in that, It also includes a fixing fixture, which is fixed to the oil pad with screws and positioned by a cylindrical pin.

10. The adaptive hydrostatic bearing according to claim 1, characterized in that, During assembly, do not install the self-feedback throttle first. First, install the fixing fixture and position it on the oil pad with screws and cylindrical pins. After installing the adaptive hydrostatic bearing on the turntable or hydrostatic guide rail, remove the fixing fixture and install the feedback throttle on the oil pad. Install the return oil baffle on the oil pad with screws and apply sealant to the connection to prevent oil leakage. Finally, install the oil inlet pipe connector to the oil inlet of the oil pad.

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