CN110039330A - A kind of high thrust enclosed gas-static turntable - Google Patents

Abstract

The invention belongs to super hot investment casting apparatus fields, combine enclosed gas-static turntable more particularly to a kind of radial thrust, more particularly to a kind of high thrust enclosed gas-static turntable, upper end inside the shell is fixedly connected with including air-bearing stator, upper thrust plate, Work piece rotary disc, transverse bearing, shell, lower thrust plate, rotor shaft, seal base, damper, flow controller I and flow controller II, the air-bearing stator；The lower end fixed connection and sealing bottom plate of the shell；The transverse bearing interference fit is connected in air-bearing stator；The upper and lower ends of the transverse bearing are fixedly connected with upper thrust plate and lower thrust plate respectively；The upper end of the upper thrust plate is fixedly connected with Work piece rotary disc；The lower end of the lower thrust plate is fixedly connected with rotor shaft；The present invention while improving gas-static turntable bearing capacity and can guarantee certain rigidity, meet the requirement of high-bearing capacity precision manufactureing equipment.

Description

A high thrust closed gas static pressure turntable

technical field

The invention belongs to the field of ultra-precision manufacturing equipment, in particular to a radial thrust combined closed gas static pressure turntable, in particular to a high thrust closed gas static pressure turntable.

Background technique

In the field of ultra-precision machining, measuring instruments are particularly important. Aerostatic bearings are widely used on measuring turntables because of their high precision and no pollution. However, due to the compressibility of the gas, the bearing capacity and stiffness of the gas hydrostatic bearing are low, so that the performance of the turntable cannot meet the requirements of high-precision and large-load applications.

The gas static pressure bearing in the prior art has the following problems:

(1) The problem of insufficient bearing capacity, increasing the air supply pressure will easily lead to the self-excited vibration of the air hammer and loss of stability;

(2) When the bearing capacity of the aerostatic bearing is increased, a large amount of stiffness will be lost, thereby reducing the accuracy of the turntable.

The above problems have led to the fact that the existing aerostatic bearing technology cannot meet the requirements of high bearing capacity precision manufacturing equipment, such as aerospace simulation test equipment, roundness meters, etc.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-thrust closed gas static pressure turntable, which can effectively solve the problems in the prior art, can improve the bearing capacity of the gas static pressure turntable while ensuring a certain rigidity, and meet the requirements of high bearing capacity precision manufacturing equipment usage requirements.

The object of the present invention is achieved through the following technical solutions:

A high thrust closed gas static pressure turntable, comprising an air bearing stator, an upper thrust plate, a workpiece turntable, a radial bearing, a casing, a lower thrust plate, a rotor shaft, a sealing bottom plate, a damper, a restrictor, and Restrictor II, the air bearing stator is fixedly connected to the upper end of the inner side of the casing; the lower end of the casing is fixedly connected to the sealing bottom plate; the radial bearing is connected in the air bearing stator with an interference fit; the radial bearing The upper and lower ends of the upper and lower thrust plates are respectively fixedly connected to the upper thrust plate and the lower thrust plate; the upper end of the upper thrust plate is fixedly connected to the workpiece turntable; the lower end of the lower thrust plate is fixedly connected to the rotor shaft;

The air bearing stator, the upper thrust plate, the lower thrust plate, the radial bearing and the rotor shaft are all annular, and the workpiece turntable is circular; the upper thrust plate, the radial bearing and the lower thrust plate are fixedly connected , to ensure that the centerlines of the three are highly overlapped, and at the same time, adjust the axial distance between the upper thrust plate and the lower thrust plate, adjust the axial distance during assembly, and adjust the upper thrust plate, radial bearing and lower thrust plate. Then make a fixed connection. The upper surface of the workpiece turntable is perpendicular to the center line of the upper thrust plate, the rotor rotating shaft is arranged at the center of the lower thrust plate, and the center lines of the two are coincident.

A plurality of throttle holes and a plurality of damping holes are evenly distributed on the upper surface of the air bearing stator along the circumferential direction, and the damping holes are located outside the throttle holes; The throttles I are connected through the tiny grooves I milled along the circumferential direction on the upper surface of the air bearing stator; a damper is fixedly connected to each of the plurality of damping holes, and the plurality of dampers are connected through the air bearing stator. The micro grooves II milled on the surface along the circumferential direction are connected; the throttle I and the damper in the same radial direction are connected through the micro grooves III milled along the radial direction on the upper surface of the air bearing stator; the air float The inner ring surface of the bearing stator is provided with a plurality of radial mounting holes in upper and lower rows, and a restrictor II is fixedly connected to each of the plurality of radial mounting holes.

The pressure gas enters the gap between the upper thrust plate and the upper surface of the air bearing stator through the restrictor I and the damper on the upper surface of the air bearing stator to form a thrust film of the floating gas static pressure bearing. The throttle I and damper on the upper surface of the stator and the upper surface of the air bearing stator constitute the floating gas static pressure thrust bearing.

The pressure gas enters the radial bearing from the restrictor II and forms the radial gas static pressure bearing air film between the inner ring surface of the stator of the air bearing. Radial gas static pressure bearing is composed of radial bearing, air bearing stator inner ring surface and restrictor II. In addition, the pressure gas enters the gap between the upper surface of the air bearing stator and the upper thrust plate, and from the gap between the inner ring surface of the air bearing stator and the radial bearing into the gap between the lower surface of the air bearing stator and the lower thrust plate to form a static pressure stop of the lower floating gas. Push the air film. The lower surface of the air bearing stator and the lower thrust plate constitute the lower floating gas static pressure thrust bearing. A closed-type aerostatic thrust bearing is formed by an upper floating aerostatic thrust bearing and a lower floating aerostatic thrust bearing.

The high-thrust closed gas static pressure turntable further includes a drive module and a measurement module; the drive module is drivingly connected to the rotor shaft; the measurement module is fixedly connected to the lower end of the inner casing, and the rotor shaft is located inside the measurement module.

The centerlines of the air bearing stator, the upper thrust plate, the radial bearing, the lower thrust plate and the rotor shaft coincide.

The upper surface of the workpiece turntable is perpendicular to the centerline of the upper thrust plate.

The diameter of the upper thrust plate is larger than that of the lower thrust plate.

The drive module adopts a torque motor.

The measuring module adopts a circular grating component.

The restrictor I is arranged along the axial direction of the air bearing stator.

The restrictor II is arranged along the radial direction of the air bearing stator.

The beneficial effects of the present invention are as follows: the high-thrust closed gas static pressure turntable of the present invention can effectively solve the problems in the prior art, and can improve the bearing capacity of the gas static pressure turntable while ensuring a certain rigidity, so as to meet the requirements of high bearing capacity. Requirements for the use of force precision manufacturing equipment.

Compared with the prior art, the beneficial effects of the present invention are:

1) The use of a larger diameter upper thrust plate and a smaller diameter lower thrust plate is conducive to improving the bearing capacity of the closed gas static pressure thrust bearing, and at the same time has a certain rigidity to ensure the accuracy of the turntable.

2) The radial thrust combined with the closed gas static pressure bearing structure (that is, the combination of the radial cylindrical bearing and the upper and lower plane thrust bearings) is beneficial to improve the machining accuracy and thus the accuracy and rotation accuracy of the turntable.

3) Adopting the structure scheme that the lower surface of the air bearing stator does not have orifices, and the air film of the upward floating air static pressure bearing and the air film of the radial air static pressure bearing are used to supply air to the downward floating air static pressure thrust bearing, which can further Improve the bearing capacity of the turntable, and at the same time can greatly reduce the gas consumption.

4) Small grooves are opened on the upper surface of the air bearing stator to uniformly expand the high pressure area of the thrust gas film of the floating gas static pressure bearing, thereby improving the bearing capacity and stiffness of the floating gas static pressure thrust bearing, and finally improving the gas static pressure. The purpose of pressing the bearing capacity of the turntable and ensuring a certain rigidity.

5) Damping holes are arranged on the upper surface of the air bearing stator, which can effectively avoid the phenomenon of "air hammer" self-excited vibration and improve the stability of the gas static pressure bearing.

To sum up, the present invention can meet the performance requirements of the high-load-carrying precision manufacturing equipment for measuring large-mass workpieces, such as aerospace simulation testing equipment, roundness meters, and the like.

Description of drawings

Fig. 1 is the overall structure front view of the present invention;

FIG. 2 is a plan view of a partial structure of the present invention.

In the figure: air bearing stator 1; micro groove I1-1; micro groove II1-2; micro groove III1-3; throttle hole 1-4; damping hole 1-5; upper thrust plate 2; workpiece Turntable 3; Radial bearing 4; Shell 5; Lower thrust plate 6; Rotor shaft 7;

Detailed ways

The present invention will be further described in detail below in conjunction with accompanying drawings 1-2.

Specific implementation one:

As shown in Figure 1-2, a high-thrust closed gas static pressure turntable includes an air bearing stator 1, an upper thrust plate 2, a workpiece turntable 3, a radial bearing 4, a housing 5, a lower thrust plate 6, The rotor shaft 7, the sealing bottom plate 8, the damper, the throttle I and the throttle II, the air bearing stator 1 is fixedly connected to the upper end of the inner side of the casing 5; the lower end of the casing 5 is fixedly connected to the sealing bottom plate 8; The radial bearing 4 is connected in the air bearing stator 1 with an interference fit; the upper and lower ends of the radial bearing 4 are respectively fixedly connected with the upper thrust plate 2 and the lower thrust plate 6 to ensure that the radial bearing 4, the upper When the centerlines of the thrust plate 2 and the lower thrust plate 6 are highly overlapped, the axial distance between the upper thrust plate 2 and the lower thrust plate 4 should be adjusted well. This compact structure is conducive to reducing the structural size and improving the machining accuracy. , the axial distance refers to the height of the radial bearing, the sum of the thickness of the upward floating gas static pressure bearing thrust film and the downward floating gas static pressure thrust film, the upward floating gas static pressure thrust film and the downward floating gas static pressure film The thrust film gap is realized by adjusting the axial distance between the upper thrust plate 2 and the lower thrust plate 6 . The upper end of the upper thrust plate 2 is fixedly connected to the workpiece turntable 3; the lower end of the lower thrust plate 6 is fixedly connected to the rotor shaft 7; 1-4 and a plurality of damping holes 1-5, the damping holes 1-5 are located on the outside of the orifice 1-4; the plurality of orifices 1-4 are respectively fixedly connected with a throttle I, and a plurality of throttles Between I is connected through the tiny grooves I1-1 on the upper surface of the air bearing stator 1; a damper is fixedly connected to each of the plurality of damping holes 1-5, and the plurality of dampers are connected through the air bearing stator 1 upper surface. The micro groove II1-2 is connected; the throttle I and the damper in the same radial direction are connected through the micro groove III1-3 on the upper surface of the air bearing stator 1; the micro groove I1-1, the micro groove II1- 2 and the structural arrangement of the micro grooves III1-3 are beneficial to improve the pressure distribution of the gas film of the gas static pressure bearing, thereby achieving the purpose of improving the performance of the gas static pressure turntable. The inner ring surface of the air bearing stator 1 is provided with a plurality of radial mounting holes in upper and lower rows, and a restrictor II is fixedly connected to each of the plurality of radial mounting holes, which is beneficial to improve the rotation accuracy and angle of the present invention. stiffness. Multiple throttles II, multiple throttles I and multiple dampers are connected by the same air path formed by micro grooves I1-1, micro grooves II1-2 and micro grooves III1-3, which is beneficial to ensure The air supply pressure is equalized to improve the angular stiffness and stability of the present invention.

The compressed air enters the gap between the upper thrust plate 2 and the upper surface of the air bearing stator 1 through the restrictor 1 and the damper on the upper surface of the air bearing stator 1 to form an upward floating gas static pressure bearing thrust film, which is formed by the upper thrust plate 2 , The upper surface of the air bearing stator 1 and the restrictor I and damper on the upper surface of the air bearing stator 1 constitute the floating gas static pressure thrust bearing.

The compressed air enters the radial bearing 4 from the restrictor II and forms the radial gas static pressure bearing air film between the inner ring surface of the air bearing stator 1 . The radial aerostatic bearing is composed of the radial bearing 4, the inner ring surface of the air bearing stator 1 and the restrictor II. In addition, the pressure gas enters the gap between the lower surface of the air bearing stator 1 and the lower thrust plate 6 from the gap between the upper surface of the air bearing stator 1 and the upper thrust plate 2, and from the gap between the inner ring surface of the air bearing stator 1 and the radial bearing 4 A static pressure thrust gas film of the floating gas is formed. The lower surface of the air bearing stator 1 and the lower thrust plate 6 constitute the lower floating gas static pressure thrust bearing. A closed-type aerostatic thrust bearing is formed by an upper floating aerostatic thrust bearing and a lower floating aerostatic thrust bearing.

When working, the compressed air enters the restrictor I and damper on the upper surface of the air bearing stator 1 through the air path, and forms an upward floating gas static pressure bearing air film between the upper thrust plate 2 and the upper surface of the air bearing stator 1. , the structure of the micro grooves I1-1, the micro grooves II1-2 and the micro grooves III1-3 on the upper surface of the air bearing stator 1 is beneficial to improve the pressure distribution of the air film of the floating aerostatic pressure bearing, thereby improving the air The pressure integral of the membrane is the bearing capacity; the compressed gas enters the radially arranged restrictor II at the same time, forming a radial gas static pressure bearing gas film on the inner ring surface of the air bearing stator 1 and the outer ring surface of the radial bearing 4. Between the air bearing stator 1 and the lower thrust plate 6, a lower floating gas static pressure bearing gas film is formed. Since the gas of the downward floating gas static pressure bearing gas film comes from the upper thrust gas film and the radial bearing gas film, there is no joint. The flow hole is used to supply air, so the pressure integral of the air film of the floating gas static pressure bearing is small, which is beneficial to improve the bearing capacity of the entire closed gas static pressure bearing. In addition, the diameter of the lower thrust plate 6 is smaller than the diameter of the upper thrust plate 2, which further increases the bearing capacity of the entire closed gas static pressure bearing, thereby improving the bearing capacity of the gas static pressure turntable.

Specific implementation two:

As shown in FIG. 1-2 , the high-thrust closed gas static pressure turntable further includes a drive module and a measurement module; the drive module is drivingly connected to the rotor shaft 7 ; the measurement module is fixedly connected to the inner side of the housing 5 . At the lower end, the rotor shaft 7 is located inside the measurement module. The driving and measurement of the high-thrust closed gas static pressure turntable are completed by the driving module and the measurement module. The content of this part is conventional content, not the main content of the present invention, so it is only briefly introduced.

Specific implementation three:

As shown in Figure 1-2, the centerlines of the air bearing stator 1, the upper thrust plate 2, the radial bearing 4, the lower thrust plate 6, and the rotor shaft 7 overlap, and the structure is compact, which is conducive to reducing the size of the structure. Improve machining accuracy.

Specific implementation four:

As shown in Figures 1-2, the upper surface of the workpiece turntable 3 is vertically arranged with the center line of the upper thrust plate 2, and the upper surface of the workpiece turntable 3 is vertically installed with the center line of the upper thrust plate 2 to ensure measurement accuracy.

Specific implementation five:

As shown in FIG. 1-2 , the diameter of the upper thrust plate 2 is larger than the diameter of the lower thrust plate 6 .

Specific implementation six:

As shown in Figure 1-2, the drive module adopts a torque motor, or a flexible coupling can be used to drive with a general motor, which can be selected according to specific needs.

Specific implementation seven:

As shown in Figures 1-2, the measurement module adopts a circular grating component 9.

Eighth specific implementation:

As shown in FIGS. 1-2 , the restrictor I is arranged along the axial direction of the air bearing stator 1 .

Specific implementation nine:

As shown in FIGS. 1-2 , the restrictor II is arranged along the radial direction of the air bearing stator 1 .

The working principle of the present invention is: when working, the compressed air enters the restrictor 1 and the damper on the upper surface of the air bearing stator 1 through the air path, and forms between the upper thrust plate 2 and the upper surface of the air bearing stator 1 The structure of the air film of the floating aerostatic bearing, the micro groove I1-1, the micro groove II1-2 and the micro groove III1-3 on the upper surface of the air bearing stator 1 is beneficial to improve the air film of the floating aerostatic bearing Then the pressure integral of the gas film is improved, that is, the bearing capacity; the compressed gas enters the radially arranged restrictor II at the same time, and forms a radial direction on the inner ring surface of the air bearing stator 1 and the outer ring surface of the radial bearing 4. Aerostatic bearing gas film. Between the air bearing stator 1 and the lower thrust plate 6, a lower floating gas static pressure bearing gas film is formed. Since the gas of the downward floating gas static pressure bearing gas film comes from the upper thrust gas film and the radial bearing gas film, there is no joint. The flow hole is used to supply air, so the pressure integral of the air film of the floating gas static pressure bearing is small, which is beneficial to improve the bearing capacity of the entire closed gas static pressure bearing. In addition, the diameter of the lower thrust plate 6 is smaller than the diameter of the upper thrust plate 2, which further increases the bearing capacity of the entire closed gas static pressure bearing, thereby improving the bearing capacity of the gas static pressure turntable.

Of course, the above description does not limit the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those of ordinary skill in the art within the essential scope of the present invention also belong to the present invention. protected range.

Claims (9)

1. A high thrust closed gas static pressure turntable, comprising an air bearing stator (1), an upper thrust plate (2), a workpiece turntable (3), a radial bearing (4), a housing (5), a lower stop Push plate (6), rotor shaft (7), sealing bottom plate (8), damper, throttle I and throttle II, characterized in that: the air bearing stator (1) is fixedly connected to the housing (5) ) inside the upper end; the lower end of the casing (5) is fixedly connected to the sealing bottom plate (8); the radial bearing (4) is connected to the air bearing stator (1) with an interference fit; the radial bearing (4) ) are fixedly connected to the upper thrust plate (2) and the lower thrust plate (6) respectively; the upper end of the upper thrust plate (2) is fixedly connected to the workpiece turntable (3); the lower thrust plate The lower end of (6) is fixedly connected to the rotor shaft (7); the upper surface of the air bearing stator (1) is evenly distributed along the circumferential direction with a plurality of throttle holes (1-4) and a plurality of damping holes (1-5) , the orifice (1-5) is located on the outer side of the throttle hole (1-4); a throttle I is fixedly connected in the multiple throttle holes (1-4) respectively, and the air passes between the multiple throttles I The tiny grooves I (1-1) on the upper surface of the floating bearing stator (1) are connected to each other; a damper is fixedly connected to each of the plurality of damping holes (1-5), and the plurality of dampers are connected through the air bearing stator (1). ) The tiny grooves II (1-2) on the upper surface are connected; the throttle I and the damper in the same radial direction are connected through the tiny grooves III (1-3) on the upper surface of the air bearing stator (1); The inner annular surface of the air bearing stator (1) is provided with a plurality of radial installation holes in two rows up and down, and a restrictor II is fixedly connected to the plurality of radial installation holes respectively. 2. A high-thrust closed-type gas static pressure turntable according to claim 1, characterized in that: the high-thrust closed-type gas-static pressure turntable further comprises a drive module and a measurement module; the drive module drives the The rotor shaft (7) is connected; the measurement module is fixedly connected to the lower end of the inner side of the casing (5), and the rotor shaft (7) is located inside the measurement module. 3. A high thrust closed gas static pressure turntable according to claim 1, characterized in that: the air bearing stator (1), the upper thrust plate (2), the radial bearing (4), the lower The centerlines of the thrust plate (6) and the rotor shaft (7) coincide. 4 . The high-thrust closed gas static pressure turntable according to claim 1 , wherein the upper surface of the workpiece turntable ( 3 ) is vertically arranged with the center line of the upper thrust plate ( 2 ). 5 . 5 . The high-thrust closed-type gas static pressure turntable according to claim 1 , wherein the diameter of the upper thrust plate ( 2 ) is larger than the diameter of the lower thrust plate ( 6 ). 6 . 6 . The high-thrust closed gas static pressure turntable according to claim 1 , wherein the drive module adopts a torque motor. 7 . 7 . The high-thrust closed gas static pressure turntable according to claim 1 , wherein the measurement module adopts a circular grating component ( 9 ). 8 . 8. A kind of high-thrust closed gas static pressure turntable according to claim 1, characterized in that: the restrictor 1 is arranged along the axial direction of the air bearing stator (1). 9 . The high-thrust closed gas static pressure turntable according to claim 1 , wherein the restrictor II is arranged along the radial direction of the air bearing stator ( 1 ). 10 .