CN105202028A - Pressure-feed air bearing provided with elastic damping air chambers - Google Patents

Abstract

The invention discloses a static pressure air bearing with an elastic damping air chamber. A cavity is arranged in the static pressure air bearing, an elastic thin plate is arranged in the cavity, and two upper and lower relatively independent bearings are formed by the elastic thin plate. The damping air chamber is provided with a first annular gasket on the inner wall of the upper damping air chamber, and a second annular gasket is arranged on the inner wall of the lower damping air chamber. The invention increases the flexible change of the elastic thin plate to adjust the volume change ratio of the damping air chamber. This self-adaptive adjustment method is simple and efficient, can greatly reduce the impact of external impact and air hammer, and increase the stiffness and stability of the static pressure air bearing. It is suitable for various ultra-precision testing fields.

Description

Hydrostatic air bearing with elastic damping chamber

technical field

The invention belongs to the technical field of ultra-precision equipment and testing, and in particular relates to a static pressure air bearing with an elastic damping air chamber.

Background technique

The performance of precision and ultra-precision machining and measuring equipment is an important indicator to measure a country's precision and ultra-precision machinery manufacturing capabilities, and it has strategic significance to drive the overall situation. Shafting and guide rails are the basic key components that determine the performance of precision and ultra-precision mechanical equipment, and bearings are the core of shafting and guide rails. In order to improve the performance of precision and ultra-precision mechanical equipment, the application of gas-lubricated bearings is becoming more and more extensive, and the research on gas-lubricated bearings has been paid more and more attention.

Due to the significant compressibility and extremely low viscosity of gas, the properties of such bearings such as stiffness, damping and load carrying capacity are much lower than those of liquid lubricated bearings. Therefore, the performance weakness of gas-lubricated bearings in processing and manufacturing equipment such as precision machinery, optical parts, and integrated circuit chips has become a bottleneck that limits the wide application of related equipment. Therefore, how to creatively improve the stiffness, damping and stability of gas-lubricated bearings has become a key scientific issue that has received more and more attention in the research of gas-lubricated bearings.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a static pressure air bearing with an elastic damping air chamber.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

An embodiment of the present invention provides a static pressure air bearing with an elastic damping air chamber. A cavity is arranged in the static pressure air bearing, and an elastic thin plate is arranged in the cavity, and two upper and lower opposite sides are formed by the elastic thin plate. An independent damping air chamber, a first annular gasket is arranged on the inner wall of the upper damping air chamber, and a second annular gasket is arranged on the inner wall of the lower damping air chamber.

In the above solution, damping holes are provided on the elastic thin plate, and 1-2 damping holes are provided, and the shape of the damping holes is rectangular or circular.

In the above scheme, the bottom surface of the static pressure air bearing is provided with 4-12 restrictors, and each restrictor is provided with an orifice, and the restrictors are connected by a pressure equalizing groove, and the equalizing The pressure groove adopts a straight line or a curve.

In the above solution, the volume of the upper damping air chamber is greater than or equal to the volume of the lower damping air chamber.

Compared with prior art, the beneficial effect of the present invention:

The invention increases the flexible change of the elastic thin plate to adjust the volume change ratio of the damping air chamber. This self-adaptive adjustment method is simple and efficient, can greatly reduce the impact of external impact and air hammer, and increase the stiffness and stability of the static pressure air bearing. It is suitable for various ultra-precision testing fields.

Description of drawings

Fig. 1 is a schematic structural view of a static pressure air bearing with an elastic damping air chamber provided by an embodiment of the present invention;

Fig. 2 is A-A to sectional view among the figure;

Figure 3 is a partial enlarged view of B in an equilibrium state;

Figure 4 is a partial enlarged view of B when the aerostatic bearing is subjected to an external positive impact;

Fig. 5 is a partial enlarged view of B when the aerostatic bearing is subjected to external reverse impact.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

The embodiment of the present invention provides a static pressure air bearing with an elastic damping air chamber. As shown in Figures 1 and 2, a cavity is arranged in the static pressure air bearing 1, and an elastic thin plate 3 is arranged in the cavity and Two upper and lower relatively independent damping air chambers are formed by the elastic thin plate 3 , a first annular gasket 2 is arranged on the inner wall of the upper damping air chamber, and a second annular gasket 4 is arranged on the inner wall of the lower damping air chamber.

After the first annular gasket 2 , the second annular gasket 4 and the elastic thin plate 3 are integrally fixed, they are installed into the static pressure air bearing 1 .

The elastic thin plate 3 is provided with a damping hole 8, and the said damping hole 8 is provided with 1-2 pieces, and its shape is rectangular or circular.

The bottom surface of the static pressure air bearing 1 is provided with 4-12 throttles 7, and each throttle 7 is provided with a throttle hole 6, and the throttles 7 are connected by a pressure equalizing groove. The equalizing groove adopts a straight line or a curve.

The volume of the upper damping air chamber is greater than or equal to the volume of the lower damping air chamber.

In actual work, the high-pressure air flows out from the restrictor 7, and forms an air film gap with a very small thickness with the bearing surface. In this air film gap, part of the high-pressure air flows into the external environment, and the other part of the high-pressure air enters in the reverse direction. In the lower damping air chamber, gas fills the upper damping air chamber through the damping air holes 8, and the rest of the air flow flows into the external environment. When the supported body of the air bearing is impacted by the outside, the static pressure air bearing 1 also vibrates up and down accordingly. The elastic thin plate 3 in the present invention can regulate the volume ratio of the upper and lower damping air chambers.

As shown in FIG. 3 , the schematic diagram when there is no impact in normal work or when the impact reaches a stable state, the elastic thin plate 3 is in a balanced position without deformation, that is, the volume of the upper and lower damping air chambers does not change, and the upper and lower damping air chambers The volume ratio of the chamber remains unchanged, and the pressure of the upper and lower damping chambers is equal.

As shown in Figure 4, when the air static pressure bearing is positively impacted by the outside world, the air mold gap between the static pressure air bearing 1 and the support base becomes smaller rapidly, and a high pressure is instantaneously formed in the lower damping air chamber, which is greater than that of the upper damping air chamber. The pressure in the damping air chamber, the instantaneous pressure of the lower damping air chamber is greater than the pressure of the upper damping air chamber, so the elastic thin plate 3 is pressed to deform, and the elastic thin plate 3 protrudes upwards, and the volume of the upper damping air chamber is pressed to decrease. On the contrary, the lower damping air chamber The volume of the chamber increases, and the volume ratio of the upper and lower damping chambers decreases, which can buffer the impact of the external impact on the aerostatic bearing 1 itself to a certain extent; as the air in the lower damping chamber enters the upper damping chamber through the damping hole The volume of the upper damping air chamber increases, and the pressure of the upper and lower damping air chambers tends to balance, so the volume ratio of the upper and lower damping air chambers returns to the original equilibrium position, and the deformation of the elastic thin plate 3 disappears, so that the air static pressure bearing tends to in a state of balance.

As shown in Figure 5, when the air static pressure bearing is subjected to external reverse impact, the air mold gap between the static pressure air bearing 1 and the support base increases rapidly, the pressure of the lower damping air chamber decreases, and the pressure of the upper damping air chamber The instantaneous pressure is greater than the pressure of the lower damping air chamber, thereby pressing the elastic thin plate 3 to be concave, and the volume ratio of the upper damping air chamber and the lower damping air chamber increases; as the air in the upper damping air chamber enters the lower damping air chamber through the damping air hole 8 The pressure of the upper damping air chamber decreases, and the pressure of the upper and lower damping air chambers tends to balance, so the volume ratio of the upper and lower damping air chambers returns to the original equilibrium position, and the deformation of the elastic thin plate 3 disappears, so that the static pressure air bearing 1 Tends to a state of balance.

Therefore, the present invention can dynamically adjust the volume ratio of the upper and lower damping air chambers, can effectively increase the damping of the aerostatic bearing, and increase its working stability.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (4)

1. A static pressure air bearing with an elastic damping air chamber, characterized in that a cavity is arranged in the static pressure air bearing (1), and an elastic thin plate (3) is arranged in the cavity and passes through the The elastic thin plate (3) forms two upper and lower relatively independent damping chambers, the inner wall of the upper damping chamber is provided with a first annular gasket (2), and the inner wall of the lower damping chamber is provided with a second annular gasket (4). 2. The static pressure air bearing with elastic damping air chamber according to claim 1, characterized in that: said elastic thin plate (3) is provided with a damping hole (8), and said damping hole (8) is provided with 1 ~2, which are rectangular or round in shape. 3. The static pressure air bearing with elastic damping air chamber according to claim 1 or 2, characterized in that: the bottom surface of the static pressure air bearing (1) is provided with 4-12 restrictors (7) Each restrictor (7) is provided with an orifice (6), and the restrictors (7) are connected by a pressure equalizing groove, and the pressure equalizing groove adopts a straight line or a curve. 4. The static pressure air bearing with an elastic damping air chamber according to claim 3, wherein the volume of the upper damping air chamber is greater than or equal to the volume of the lower damping air chamber.