Dynamic pressure air bearing gyro motor quasi-dynamic inflation replacement device and replacement method

Abstract

The invention relates to a dynamic pressure air bearing gyro motor quasi-dynamic inflation replacement device and a replacement method. The device comprises an inflation unit, an exhaust unit and a vacuum degree detection unit, the inflating unit is used for sequentially inflating nitrogen and helium into the gyro motor sealing running tank in the motor stage and sequentially inflating nitrogen and helium into the buoy in the floater stage; the air exhaust unit is used for exhausting air in the gyro motor sealing running tank after the gyro motor runs in the gyro motor sealing running tank in a motor stage, so that pollutants among matched parts of the gyro motor are discharged; in the inflation stage of the floater, after the gyro motor operates in the buoy, air in the buoy is pumped out through the air pumping unit, and pollutants at all positions of the inner wall of the buoy and the gyro motor are discharged; the vacuum degree detection unit is used for realizing the vacuum degree detection of the sealed running of the gyro motor and the in-tank air exhaust stage in the motor stage; and the vacuum degree detection in the buoy in the air exhaust stage is realized in the floater air inflation stage. According to the invention, pollutants in the gyro motor can be thoroughly removed.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrodynamic bearing gyro motors, and specifically relates to a quasi-dynamic inflation replacement device and replacement method for hydrodynamic air bearing gyro motors, which are used to solve the problem of early cleaning of gyro motor bearing pollutants to ensure the reliability of long-term operation of the bearings. Background Art

[0002] High-precision three-floating gyros and liquid-floating gyros all use gas dynamic pressure bearing gyro motors. The dynamic pressure air bearing has no external gas source. It uses the viscosity of the gas medium to bring the gas into the micron-level gap when the rotor moves. The rotor shaft hole eccentricity and the spiral groove structure form radial and axial dynamic pressure support to achieve contactless suspension between the rotor and the stator, and the theoretical operating life is infinite. Since the realization of the dynamic pressure effect depends on the air film velocity gradient formed after the relative movement of the stator and rotor, the air film must usually be as small as the micron level to reflect a certain support stiffness. The dimensional accuracy of the micron level requires the shape and position accuracy of the submicron level. Trace pollutants in the environmental medium will have a fatal effect on the bearing. In the actual operation of the dynamic pressure air bearing, due to the start-stop wear, wear particles will form pollutants in the bearing. At the same time, the gyro motor is assembled in the inner cavity of the float, and the volatilization effect of non-metallic materials in its operating environment will also produce pollutants. Therefore, there will always be pollutants accumulated in the bearing. After long-term operation, the pollution accumulates to a certain extent, causing the bearing to have a reduced starting performance or even unable to start. For this reason, the pollutants in the bearing must be controlled.

[0003] The hydrodynamic bearing is composed of a thrust bearing and a radial bearing. The working principle of the radial bearing: when the rotor is stationary, the rotor shaft hole is in line contact with the motor shaft; when the rotor rotates, it drives the gas in the gap to move together. When the moving gas medium approaches the smaller gap, the gas is compressed to form a wedge-shaped gas film and a corresponding high-pressure area. The rotor accelerates and the gas film holds up the rotor. The rotor and the shaft form a hydrodynamic support gas film without mechanical contact, forming a radial bearing. The working principle of the thrust bearing: the rotor is dragged by the motor and begins to rotate. The gas on the outer edge of the thrust plate is also driven to rotate and pumped into the bearing along the spiral groove. When the gas enters the root of the groove, it is blocked by the steps of the groove, resulting in an increase in pressure. As the rotor speed increases, the pressure continues to increase. When the pressure increases to a certain value, the rotor is lifted up, and a hydrodynamic support gas film without mechanical contact is formed between the rotor thrust surface and the thrust plate, forming a thrust bearing. The principles of radial and axial bearings are described in detail respectively. Figure 4Left and right. There are three common methods for controlling bearing contamination. One is to use high-hardness and friction-resistant materials to reduce material wear during the start-stop process of the motor. The second is to use low-volatile materials inside the entire float or to vacuum exhaust the components before assembly. The third is to improve the surface quality of parts, strengthen the cleaning of parts, and reduce the pollutants brought into the float during assembly. The above measures have been taken by various research institutions and manufacturers, but these methods can only suppress pollution. Considering that the bearing clearance is only in the order of 1μm-3μm, even very small amounts of pollutants will still affect the bearings. Therefore, new improvement measures are still needed to ensure the life requirements of the motor for high-precision and long-life gyroscopes. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a quasi-dynamic inflation replacement device and a replacement method for a dynamic pressure air floating bearing gyro motor.

[0005] One of the above objects of the present invention is achieved by the following technical solution:

[0006] A quasi-dynamic inflation replacement device for a dynamic pressure air bearing gyro motor, comprising an inflation unit, an air extraction unit and a vacuum degree detection unit;

[0007] The inflation unit is used to successively fill nitrogen and helium into the sealing run and tank of the gyro motor in the motor stage, and to successively fill nitrogen and helium into the buoy in the float stage; the exhaust unit is used to, in the motor stage, after the gyro motor runs in the sealing run and tank of the gyro motor, exhaust the gas in the sealing run and tank of the gyro motor to discharge pollutants between the matching parts of the gyro motor; and in the float inflation stage, after the gyro motor runs in the buoy, exhaust the gas in the buoy through the exhaust unit to discharge pollutants from various parts of the inner wall of the buoy and the gyro motor itself; the vacuum detection unit is used to detect the vacuum in the sealing run and tank of the gyro motor in the exhaust stage in the motor stage; and to detect the vacuum in the buoy in the exhaust stage in the float inflation stage.

[0008] Moreover, the inflation unit adopts two inflation branches arranged in parallel, and a secondary pressure reducing valve, a manual fine-tuning valve and an inflation valve are installed in sequence on the pipeline of each inflation branch. The front ends of the two inflation branches are connected to respective air sources, and the rear ends of the two inflation branches are connected to form a common inflation output end. The secondary pressure reducing valve is used to reduce the air supply pressure, the manual fine-tuning valve is used to achieve precise adjustment of the air supply pressure, and the inflation valve is used to achieve the switch of the corresponding inflation branch.

[0009] Moreover, the air extraction unit adopts a single-pipeline structure, including an air venting valve and a dry pump, and the air venting valve and the dry pump are successively installed on the air extraction pipeline.

[0010] Furthermore, the vacuum degree detection unit adopts a vacuum gauge.

[0011] The second objective of the present invention is achieved by the following technical solutions:

[0012] A method for quasi-dynamic inflation and replacement of a gyro motor of a dynamic pressure air floating bearing based on the quasi-dynamic inflation and replacement device of the gyro motor of a dynamic pressure air floating bearing, wherein the process flow of the inflation and replacement method is set as follows: after the gyro motor is finely assembled, an inflation and replacement operation of the motor stage is performed; after the motor test is completed, the frame is mounted and the float is sealed according to the normal process; before the float is engaged, an inflation and replacement operation of the float stage is performed; after the test is qualified, the gyro motor is delivered.

[0013] Moreover, the inflation and replacement in the motor stage is the first inflation and replacement stage, and the inflation and replacement in the float stage is the second inflation and replacement stage;

[0014] The first inflation phase includes:

[0015] 1.1. Install the gyro motor into the gyro motor sealing runner and tank;

[0016] 1.2. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct;

[0017] 1.3. Adjust the gyro motor seal and the temperature inside the tank to the set temperature, the set temperature range is 20℃~80℃;

[0018] 1.4. Connect the front end of the pipeline of the vacuum unit to the reserved air port on the gyro motor sealing runner and tank; then complete the first runner and tank vacuuming through the vacuum unit according to normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute;

[0019] 1.5. Connect the inflation output end of the inflation unit to the gyro motor sealing runner and the reserved gas port in the tank, and fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the exhaust unit is in the closed state;

[0020] 1.6. Turn on the gyro motor. After the gyro motor is synchronized, continue to run for 2 minutes. Turn off the gyro motor and make the motor stop steadily.

[0021] 1.7. Repeat the above vacuuming and inflation cycle 3 more times;

[0022] 1.8. Pump out air for the fifth time;

[0023] 1.9, filled with helium, inflation to 101kPa;

[0024] 1.10. After inflation, for the hardcover running and tank motors, hand them over to the motor tester to complete the subsequent work;

[0025] The second inflation phase includes:

[0026] 2.1. Install the gyro motor into the buoy;

[0027] 2.2. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct; confirm that the motor is rotating in the correct direction indicated by the design;

[0028] 2.3. Adjust the temperature inside the float to the set temperature, which is 70°C;

[0029] 2.4. Connect the front end of the pipeline of the air extraction unit to the reserved air port on the float; then complete the first air extraction of the float through the air extraction unit according to the normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute;

[0030] 2.5. Connect the inflation output end of the inflation unit to the reserved air port on the buoy, and fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the air extraction unit is in the closed state;

[0031] 2.6. Turn on the gyro motor, and let it run for 2 minutes after it is synchronized. Then turn off the gyro motor and let it stop steadily.

[0032] 2.7 Repeat the above vacuuming and inflation cycle 3 more times;

[0033] 2.8 Carry out the fifth gas extraction;

[0034] 2.9. Inflate with helium to a pressure of 101 kPa. After inflation, complete the float clamping and testing work according to the existing process and test specifications.

[0035] The advantages and positive effects of the present invention are:

[0036] The present invention aims to solve the problem of removing pollutants from the hydrodynamic air bearing by adopting vacuum exhaust combined with inflation backwashing during the motor stage and the float inflation stage. The airflow flushing during the operation of the motor accelerates the removal of pollutants, which are then discharged with the next round of air extraction. This is repeated to completely remove pollutants from the closed inner cavity, thereby achieving complete removal of pollutants from the gyro motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a connection diagram of the quasi-dynamic inflation displacement device of the dynamic pressure air floating bearing gyro motor of the present invention;

[0038] Figure 2 It is a schematic diagram of the structure of the gyro motor of the present invention installed in the gyro motor sealing runner and tank;

[0039] Figure 3It is a schematic diagram of the structure of the gyro motor of the present invention installed in the buoy;

[0040] Figure 4 4a is a comparison diagram of the inertial glide time of the gyro motor of the present invention before and after treatment, 4b is a comparison diagram of the inertial glide time of the motor in the state without quasi-dynamic inflation replacement, and 4b is a comparison diagram of the inertial glide time of the motor in the state after quasi-dynamic inflation replacement. DETAILED DESCRIPTION

[0041] The structure of the present invention is further described below with reference to the accompanying drawings and by way of examples. It should be noted that the present examples are descriptive rather than restrictive.

[0042] The theoretical basis of the quasi-dynamic inflation replacement concept of the dynamic pressure air floating bearing gyro motor of the present invention is: for the movement of particles in the bearing, its analysis is applicable to the solid-gas two-phase flow model in the flow field. Fine and light particles will completely move along the streamlines in the flow field, while large-scale and high-density particles will not follow the streamlines. Therefore, first make a judgment on the appropriate movement law. When there are particles in the fluid system, select a suitable model based on the Stokes number. The Stokes number St is the ratio of the particle (discrete phase) time relaxation coefficient to the flow characteristic time scale.

[0043]

[0044] in,

[0045] D and U are the characteristic length and velocity of the flow.

[0046] If St<<1, the particles will follow the flow field.

[0047] If St>1, the particle motion is independent of the flow field.

[0048] For the model of the dynamic pressure gyro motor bearing calculation, the Stokes number is much less than 1 after the parameters are entered. The main reason is that the particles are in the micron range, and even iron materials can flow with the flow field. From the calculation, it can be seen that for pollutants that are mainly volatile, long-term static air extraction is effective, but for other parts in the inner cavity of the motor and its installed float assembly, other surface deposits and adsorption pollutants that are smaller than the bearing clearance (generally ≤3μm) will not be effectively removed when there is no gas flow.

[0049] Based on the above analysis, the present invention aims to eliminate pollutants in hydrodynamic air bearings by combining vacuum exhaust with inflation backwashing during the motor stage and float inflation stage. The airflow from the motor accelerates the fall of pollutants, which are then discharged with the next round of vacuum pumping. This process is repeated to completely eliminate pollutants in the closed cavity.

[0050] The inflation replacement process flow of the present invention is set as follows: after the gyro motor is finely assembled, the motor stage inflation replacement work is carried out; after the motor test is completed, the frame is installed according to the normal process, the float is sealed with glue, and before the float is clamped, the float stage inflation replacement work is carried out; after the test is qualified, the gyro motor is delivered.

[0051] The present invention is a quasi-dynamic inflation replacement device for a dynamic pressure air bearing gyro motor, see Figure 1 , the invention point is: it includes an inflation unit, an exhaust unit and a vacuum detection unit. The inflation unit is used to fill nitrogen and helium into the sealing runner and tank of the gyro motor in the motor stage, and fill nitrogen and helium into the float in the float stage. The inflation unit adopts two inflation branches arranged in parallel, and a secondary pressure reducing valve, a manual fine-tuning valve and an inflation valve are installed in sequence on the pipeline of each inflation branch. The front ends of the two inflation branches are connected to their respective air sources, and the rear ends of the two inflation branches are connected to form a common inflation output end. The secondary pressure reducing valve is used to reduce the air supply pressure, the manual fine-tuning valve is used to achieve precise adjustment of the air supply pressure, and the inflation valve is used to achieve the switch of the corresponding inflation branch.

[0052] The air extraction unit adopts a single pipeline structure, including a vent valve and a dry pump, which are successively installed on the air extraction pipeline. In the motor stage, after the gyro motor runs in the gyro motor sealing runner and tank, the air extraction unit is used to extract the gas in the gyro motor sealing runner and tank, so as to discharge the pollutants between the matching parts of the gyro motor; similarly, in the float inflation stage, after the gyro motor runs in the buoy, the air extraction unit is used to extract the gas in the buoy, so as to discharge the pollutants from various places on the inner wall of the buoy and the gyro motor itself.

[0053] The vacuum detection unit adopts a vacuum gauge to detect the vacuum of the gyro motor seal run and the tank during the air extraction stage in the motor stage; and to detect the vacuum of the float cylinder during the air extraction stage in the float inflation stage.

[0054] Based on the above-mentioned quasi-dynamic inflation replacement device for the gyro motor of the dynamic pressure air floating bearing, a method for quasi-dynamic inflation replacement of the gyro motor of the dynamic pressure air floating bearing is performed. The process flow of the inflation replacement method is set as follows: after the gyro motor is finely assembled, an inflation replacement operation is performed at the motor stage. After the motor test is completed, the frame is mounted according to the normal process, and the float is sealed with glue. Before the float is clamped, an inflation replacement operation is performed at the float stage. After the test is qualified, the gyro motor is delivered, wherein the inflation replacement at the motor stage is the first inflation replacement stage, and the inflation replacement at the float stage is the second inflation replacement stage.

[0055] The first inflation phase includes:

[0056] 1.1. Install the gyro motor 1 into the gyro motor sealing runner and tank 2, see Figure 2 ;

[0057] 1.2. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct;

[0058] 1.3. Adjust the gyro motor seal and the temperature inside the tank to the set temperature, the set temperature range is 20℃~80℃;

[0059] 1.4. Connect the front end of the pipeline of the vacuum unit to the reserved air port on the gyro motor sealing runner and tank; then complete the first runner and tank vacuuming through the vacuum unit according to normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute;

[0060] 1.5. Connect the inflation output end of the inflation unit to the gyro motor sealing runner and the reserved air port in the tank. The gyro motor sealing runner and the reserved air port in the tank can adopt a three-way joint structure. Fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the exhaust unit is in a closed state;

[0061] 1.6. Turn on the gyro motor, and let it run for 2 minutes after it is synchronized. Turn off the gyro motor and let it stop (about 3 minutes).

[0062] 1.7. Repeat the above vacuuming and inflation cycle 3 more times;

[0063] 1.8. Pump out air for the fifth time;

[0064] 1.9, filled with helium, inflation to 101kPa;

[0065] 1.10. After inflation, for the hardcover running and tank motors, hand them over to the motor tester to complete the subsequent work;

[0066] The second inflation phase includes:

[0067] 2.1. Install the gyro motor into the buoy 3, see Figure 3 ;

[0068] 2.3. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct; confirm that the motor is rotating in the correct direction indicated by the design;

[0069] 2.3. Adjust the temperature inside the float to the set temperature, which is 70°C;

[0070] 2.4. Connect the front end of the pipeline of the air extraction unit to the reserved air port 3.1 on the float; then complete the first air extraction of the float through the air extraction unit according to the normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute;

[0071] 2.5. Connect the inflation output end of the inflation unit to the air port reserved on the float. The air port reserved on the float can adopt a three-way joint structure. Fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the air extraction unit is in a closed state;

[0072] 2.6. Turn on the gyro motor, and let it run for 2 minutes after it is synchronized. Turn off the gyro motor and let it stop (about 3 minutes).

[0073] 2.7. Repeat the above vacuuming and inflation cycle 3 more times;

[0074] 2.8. Pump out air for the fifth time;

[0075] 2.9. Inflate with helium to a pressure of 101 kPa. After inflation, complete the float clamping and testing work according to the existing process and test specifications.

[0076] Record the above gyro motor / float number, operating temperature, time, etc.

[0077] After the motor is filled and replaced, the motor is tested and the motor filling and replacement status is judged based on the test results. Figure 4 The motor inertia sliding time fluctuation method is used to judge the motor quality, and the comparison result also shows the effect of the present invention.

[0078] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A quasi-dynamic inflation replacement device for a dynamic pressure air bearing gyro motor, characterized in that: It includes an air filling unit, an air extraction unit and a vacuum degree detection unit; The inflation unit is used to successively fill nitrogen and helium into the sealing run and tank of the gyro motor in the motor stage, and to successively fill nitrogen and helium into the buoy in the float stage; the exhaust unit is used to, in the motor stage, after the gyro motor runs in the sealing run and tank of the gyro motor, exhaust the gas in the sealing run and tank of the gyro motor to discharge pollutants between the matching parts of the gyro motor; and in the float inflation stage, after the gyro motor runs in the buoy, exhaust the gas in the buoy through the exhaust unit to discharge pollutants from various parts of the inner wall of the buoy and the gyro motor itself; the vacuum detection unit is used to detect the vacuum in the sealing run and tank of the gyro motor in the exhaust stage in the motor stage; and to detect the vacuum in the buoy in the exhaust stage in the float inflation stage.

2. The quasi-dynamic inflation displacement device of the dynamic pressure air bearing gyro motor according to claim 1 is characterized in that: The inflation unit adopts two inflation branches arranged in parallel, and a secondary pressure reducing valve, a manual fine-tuning valve and an inflation valve are installed in sequence on the pipeline of each inflation branch. The front ends of the two inflation branches are connected to their respective air sources, and the rear ends of the two inflation branches are connected to form a common inflation output end; the secondary pressure reducing valve is used to reduce the air supply pressure; the manual fine-tuning valve is used to achieve precise adjustment of the air supply pressure, and the inflation valve is used to realize the switching of the corresponding inflation branch.

3. The quasi-dynamic inflation displacement device of the dynamic pressure air bearing gyro motor according to claim 1, characterized in that: The air extraction unit adopts a single-pipeline structure, including an air release valve and a dry pump, and the air release valve and the dry pump are successively installed on the air extraction pipeline.

4. The quasi-dynamic inflation displacement device of the dynamic pressure air bearing gyro motor according to claim 1, characterized in that: The vacuum degree detection unit adopts a vacuum gauge.

5. A method for quasi-dynamic inflation replacement of a gyro motor of a dynamic pressure air bearing based on the quasi-dynamic inflation replacement device of a gyro motor of a dynamic pressure air bearing according to any one of claims 1 to 4, characterized in that: The process flow of the inflation replacement method is set as follows: after the gyro motor is finely assembled, the motor stage inflation replacement operation is performed first; then after the motor test is completed, the frame is mounted according to the normal process, and the float sealing process is performed before the float is clamped. The float stage inflation replacement operation is performed, and after the test is qualified, the gyro motor is delivered.

6. The method for quasi-dynamic inflation replacement of a dynamic pressure air bearing gyro motor according to claim 5, characterized in that: The inflation and replacement in the motor stage is the first inflation and replacement stage, and the inflation and replacement in the float stage is the second inflation and replacement stage; The first inflation phase includes: 1.

1. Install the gyro motor into the gyro motor sealing runner and tank; 1.

2. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct; 1.

3. Adjust the gyro motor seal and the temperature inside the tank to the set temperature, the set temperature range is 20℃~80℃; 1.

4. Connect the front end of the pipeline of the vacuum unit to the reserved air port on the gyro motor sealing runner and tank; then complete the first runner and tank vacuuming through the vacuum unit according to normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute; 1.

5. Connect the inflation output end of the inflation unit to the gyro motor sealing runner and the reserved gas port in the tank, and fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the exhaust unit is in the closed state; 1.

6. Turn on the gyro motor. After the gyro motor is synchronized, continue to run for 2 minutes. Turn off the gyro motor and make the motor stop steadily. 1.

7. Repeat the above vacuuming and inflation cycle 3 more times; 1.

8. Pump out air for the fifth time; 1.9, filled with helium, inflation to 101kPa; 1.

10. After inflation, for the hardcover running and tank motors, hand them over to the motor tester to complete the subsequent work; The second inflation phase includes: 2.

1. Install the gyro motor into the buoy; 2.

2. Connect the motor power supply, confirm the power supply voltage and frequency, and ensure that the motor can run at the rated speed; the lead wires A, B, and C correspond to red, yellow, and blue, and confirm that the phase sequence is correct; confirm that the motor is rotating in the correct direction indicated by the design; 2.

3. Adjust the temperature inside the float to the set temperature, which is 70°C; 2.

4. Connect the front end of the pipeline of the air extraction unit to the reserved air port on the float; then complete the first air extraction of the float through the air extraction unit according to the normal process and test specifications, and the vacuum gauge shows 0kPa, which is maintained for 1 minute; 2.

5. Connect the inflation output end of the inflation unit to the reserved air port on the buoy, and fill nitrogen through an inflation branch of the inflation unit to reach 101kPa. At this time, the air extraction unit is in the closed state; 2.

6. Turn on the gyro motor, and let it run for 2 minutes after it is synchronized. Then turn off the gyro motor and let it stop steadily. 2.7 Repeat the above vacuuming and inflation cycle 3 more times; 2.8 Carry out the fifth gas extraction; 2.

9. Inflate with helium to a pressure of 101 kPa. After inflation, complete the float clamping and testing work according to the existing process and test specifications.

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