Rotary table stable supporting structure in vacuum environment

Abstract

The invention relates to a rotary table stable supporting structure in a vacuum environment, and relates to the field of rotary table supporting, the rotary table stable supporting structure comprises a plurality of groups of supporting stand columns connected and combined by multi-section bolts and a mounting plate connected with the plurality of groups of supporting stand columns, the supporting stand columns are made of invar steel materials, and the total length of each group of supporting stand columns is 1.5-2m; a thermal control system is arranged outside the supporting stand column to enable the temperature change of the supporting stand column to be between 20 + / -1 DEG C; the rotary table is fixed to the top of the supporting stand column, and the bottom of the supporting stand column extends out of the vacuum tank to be fixedly connected with the air floating platform.

Description

Technical Field

[0001] The invention relates to the technical field of turntable support, and in particular to a stable support structure for a turntable in a vacuum environment. Background Art

[0002] When the three-axis turntable is installed in the vacuum tank, the intersection of the three-axis turntable axis needs to be placed at the center of the vacuum tank. Due to the large diameter of the inner cavity of the vacuum tank, the turntable needs to be installed on a support structure with a height of about 2m. In addition, the environment inside the vacuum tube is lower than 1×10-3Pa, the temperature is -173℃, and the turntable will move. The general support structure is not enough to maintain stable support. Although the thick support can resist deformation, it is too heavy due to its high density and difficulty in installation. If it is made into a slender structure, it will also shake when the turntable moves, affecting the stability of the support.

[0003] Therefore, in view of the above shortcomings, it is necessary to provide a stable support structure for a turntable in a vacuum environment. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] The technical problem to be solved by the present invention is to solve the problems of the existing simple bracket.

[0006] (II) Technical solution

[0007] In order to solve the above technical problems, the present invention provides a stable support structure for a turntable in a vacuum environment, comprising a plurality of groups of support columns connected by multi-section bolts and a mounting plate connecting the plurality of groups of support columns, the support columns are made of Invar material, the total length of each group of support columns is between 1.5 and 2 m, and a thermal control system is provided outside the support columns to ensure that the temperature of the support columns varies between 20±1°C; the turntable is fixed on the top of the support columns, and the bottom of the support columns extends out of the vacuum tank and is fixedly connected to the air flotation platform.

[0008] As a further illustration of the present invention, preferably, the supporting column is a hollow cylindrical structure, and flanges are provided at both ends of the length direction of each supporting column.

[0009] As a further illustration of the present invention, preferably, the outer diameter of the support column is between 160 and 165 mm, the outer diameter of the flange is between 200 and 210 mm, and the total length of each section of the support column is between 618 and 1000 mm.

[0010] As a further illustration of the present invention, preferably, the support pillars and the turntable are coated with a polyimide film, and the outer surface of the polyimide film is coated with a carburized black film.

[0011] As a further illustration of the present invention, preferably, an electric heating sheet and a temperature sensor are attached between the polyimide film and the supporting pillar to form a thermal control system.

[0012] (III) Beneficial effects

[0013] The above technical solution of the present invention has the following advantages:

[0014] The present invention realizes stable support of the turntable at a height of about 2m by designing a simple support structure, and meets the requirements of structural stability and thermal stability. At the same time, on the one hand, it reduces the difficulty and cost of mechanical processing, on the other hand, it facilitates the design and implementation of the thermal control system, and in addition, it can meet the needs of the vacuum tank through-cabin design, achieving multiple goals at one stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the general assembly effect diagram of the present invention;

[0016] Figure 2 is a bottom view of the present invention;

[0017] Figure 3 This is a drawing showing the assembly effect of the support column of the present invention;

[0018] Figure 4 It is a deformation cloud diagram of the support column of the present invention;

[0019] Figure 5 It is a stress cloud diagram of the support column of the present invention;

[0020] Figure 6 It is a Y-axis moment deformation cloud diagram of the support column of the present invention;

[0021] Figure 7 It is a Z-axis moment deformation cloud diagram of the support column of the present invention;

[0022] Figure 8 It is a temperature variation diagram of the support column of the present invention under the thermal control state;

[0023] Fig. 9 It is a thermal deformation cloud diagram of the support column of the present invention at 2150s under thermal control state;

[0024] Fig.10 It is a thermal deformation cloud diagram of the support column of the present invention at 6450s under thermal control state;

[0025] Fig.11 It is a diagram of thermal deformation law of the support column of the present invention under thermal control state.

[0026] In the figure: 1. Support column; 2. Mounting plate; 3. Turntable. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] A stable support structure for a turntable in a vacuum environment, combined with Figure 1 , Figure 2 , including three groups of support columns 1 connected by two or three sections of bolts and a mounting plate 2 connecting the three groups of support columns 1. The mounting plate 2 can improve the stability of the three groups of support columns 1. The turntable 3 is fixed on the top of the three groups of support columns 1, and the bottom of the three groups of support columns 1 extends out of the vacuum tank and is fixedly connected to the air flotation platform.

[0029] Combination Figure 2 , Figure 3 The support column 1 is a hollow cylindrical structure made of Invar material, and its thermal expansion coefficient is 1×10 -6 / ℃, which is much smaller than other metal materials. Flanges are provided at both ends of the length direction of each section of the support column 1. The outer diameter of the support column 1 is between 160 and 165 mm, the outer diameter of the flange is between 200 and 210 mm, the total length of each section of the support column 1 is between 618 and 1000 mm, and the total length of each group of support columns 1 is between 1.5 and 2 m. The support column 1 and the turntable 3 are coated with a polyimide film, and the outer surface of the polyimide film is coated with a carburized black film to prevent low-temperature radiation. An electric heating plate is pasted between the polyimide film and the support column 1 for heating protection, and a certain number of temperature sensors are arranged for real-time temperature monitoring. The electric heating plate and the temperature sensor together form a thermal control system to make the temperature change of the support column 1 and the turntable 3 between 20±1℃. At the same time, local cold radiation heat exchange measures are taken for the working heat source part of the turntable 3, so that the entire thermal control protection system forms an independent closed-loop real-time temperature control system to ensure that the turntable 3 can work normally in an ambient temperature of -173℃.

[0030] Through reasonable material selection and thermal control system, the influence of thermal deformation of support column 1 on the accuracy of turntable 2 can be minimized. To verify the stability of the design, a hollow cylindrical structure with a diameter of Φ650mm and a diameter of Φ800mm for the upper and lower flanges is selected. For the convenience of the experiment, only two sections of support column 1 are processed and installed. During the installation process, the two sections of support column 1 are connected together by bolts to form a stable foundation for the turntable.

[0031] According to the actual situation, the finite element model of the two-section support column 1 is constructed in the computer, and the actual weight of the turntable 3 is 590Kg. By analyzing and calculating the torque of the multi-axis turntable 3, it is determined that the three torques on the support column 1 are the horizontal x-axis: 10.175N·m, the y-axis coinciding with the axis of the support column 1: 27.775N·m, and the horizontal z-axis: 2.23N·m. The above data is imported into the ANSYS software to analyze the support column 1, and the following is obtained: Figure 4 The deformation cloud map and Figure 5 The stress cloud diagram results.

[0032] Combination Figure 4 , Figure 5 Under the load, the maximum deformation of the column is only 2.5μm, and the deformation is mainly in the y-axis direction, that is, the height direction of the supporting column 1, which will not affect the test of the turntable 3. At the same time, the internal stress is much smaller than the allowable stress of the material and will not cause structural damage.

[0033] Finally, the rotation angle change of the support column 1 under the action of the three moments is calculated to analyze the degree of its influence on the test process. Since the moments in the x-axis and z-axis directions are perpendicular to each other, the deformation of the support column 1 is the same, and the z-axis moment is much smaller than the x-axis moment. Therefore, in the calculation process, only the worst case is analyzed, that is, the moments in the z-axis direction and the y-axis direction are applied. The results are as follows: Figure 6 and Figure 7 shown.

[0034] According to Figure 6 and Figure 7 From the analysis, it can be seen that the maximum angular deformation of the support column 1 in the y-axis direction under the action of the y-axis moment is 0.038", while the maximum angular deformation of the support column 1 in the z-axis direction under the action of the z-axis moment is 0.015", which is an order of magnitude smaller than the position accuracy of the turntable 3, so it will not affect the test process of the turntable 3.

[0035] like Figure 8 As shown in Figure 1, according to the thermal control scheme of the support column 1, the temperature of the support column 1 changes in an approximately sawtooth shape under the thermal control state, with a period of 8600s and an amplitude of 20±0.5℃. In order to analyze the change law of the support column 1 under the thermal control system, a finite element model of the support column 1 is further established, and the thermal loads in two cycles are loaded onto the model, and the following is obtained: Fig. 9 The thermal deformation cloud diagram of the support column 1 at 2150s is shown in FIG. Fig.10 The thermal deformation cloud diagram of the support column 1 at 6450s is shown.

[0036] like Fig. 9 and Fig.10As shown, the deformation of the support column 1 under the action of the thermal control system is mainly along the y-axis direction, and at 2150s, the thermal deformation is along the negative direction of the y-axis, and at 6450s, the thermal deformation is along the positive direction of the y-axis.

[0037] In order to analyze the thermal deformation law of the support column 1 under the action of the thermal control system, as shown in Fig.11 As shown, the time-varying curve of thermal deformation of support column 1 is further extracted. According to the analysis of the curve, the deformation cycle of support column 1 is the same as the temperature change cycle under the thermal control system, and the maximum deformation amplitude is only 1.03 μm, which will not affect the test process.

[0038] In summary, the present invention provides a turntable support structure in a vacuum environment, which can ensure stable support for the turntable 3 at a height of about 2m, and meet the requirements of structural stability and thermal stability. In addition, the support column 1 adopts a design structure of multiple and multi-section combinations, which can reduce the difficulty and cost of mechanical processing on the one hand, facilitate thermal control design and implementation on the other hand, and can also meet the requirements of the through-cabin design of the vacuum tank, and has broad application prospects.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A stable support structure for a turntable in a vacuum environment, characterized by: The invention comprises a plurality of groups of support columns (1) connected by multi-section bolts and a mounting plate (2) connecting the plurality of groups of support columns (1); the support columns (1) are made of invar material; the total length of each group of support columns (1) is between 1.5 and 2 meters; a thermal control system is arranged outside the support columns (1) to make the temperature of the support columns (1) vary between 20±1°C; a turntable (3) is fixed on the top of the support columns (1); the bottom of the support columns (1) extends out of a vacuum tank and is fixedly connected to an air flotation platform.

2. The stable support structure for a turntable in a vacuum environment according to claim 1, characterized in that: The supporting column (1) is a hollow cylindrical structure, and flanges are provided at both ends of the length direction of each section of the supporting column (1).

3. The stable support structure for a turntable in a vacuum environment according to claim 2, characterized in that: The outer diameter of the support column (1) is between 160 and 165 mm, the outer diameter of the flange is between 200 and 210 mm, and the total length of each section of the support column (1) is between 618 and 1000 mm.

4. The stable support structure for a turntable in a vacuum environment according to claim 3, characterized in that: The support column (1) and the turntable (3) are coated with a polyimide film, and the outer surface of the polyimide film is coated with a carburized black film.

5. The stable support structure for a turntable in a vacuum environment according to claim 4, characterized in that: An electric heating sheet and a temperature sensor are pasted between the polyimide film and the supporting column (1) to form a thermal control system.

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