Ultra-stable thin-wall rotary table with ultra-large-diameter light path channel for space

Abstract

The invention discloses an ultra-stable thin-wall rotary table with an ultra-large-diameter light path channel for space, and the rotary table employs a stator-rotor-stator parallel type assembly cross section structure. The device comprises a double-row thrust angular contact ball bearing, a permanent magnet synchronous motor, an incremental inductosyn, a switch Hall sensor, a position decoder, a split conductive slip ring, a load interface and a mounting flange, the permanent magnet synchronous motor, the incremental inductosyn and the split conductive slip ring all take the double-row thrust angular contact ball bearing as installation and rotation reference; the double-row thrust angular contact ball bearing comprises a bearing inner ring and a bearing outer ring; the permanent magnet synchronous motor comprises a motor stator and a motor rotor; the incremental inductosyn comprises an inductosyn stator and an inductosyn rotor; the split type conductive slip ring comprises a conductive ring and an electric brush. Light weight and miniaturization of the rotary table are achieved, the axial length of the rotary table is reduced, and the output end direction and radial rotation precision of the rotary table is improved.

Description

Technical Field

[0001] The invention belongs to the field of space vehicles, and in particular relates to an ultra-stable thin-wall turntable with an ultra-large-aperture optical path channel for space use. Background Art

[0002] The pupil camera has working modes such as fixed pupil and rotating pupil. In order to achieve high-quality imaging recognition, high-sensitivity wide-area detection and other functions, a space-use turntable with an ultra-large aperture optical path is required to complete micrometer and sub-arcsecond movement under heavy load.

[0003] The existing patent with publication number CN116961272A discloses a two-dimensional turntable suitable for large-aperture space telescopes. The invention is a motion mechanism applied to large-aperture telescopes, used to complete tasks such as automatic capture, tracking, and aiming of space laser communications. The turntable in the invention does not have an integrated motor bearing design and a lightweight design, and has a complex structure, and cannot complete the signal and high-power electrical energy transmission function during the omnidirectional rotation process.

[0004] The existing patent with publication number CN116961272A discloses a motor-integrated hollow rotating platform. The invention uses the output end of the motor assembly to connect the drive gear through a connecting shaft, and drives the hollow rotating seat to rotate through gear meshing. The driving method of the invention through the meshing of the motor assembly, shaft, and drive gear has the disadvantages of large size and low integration. In addition, the meshing gears will loosen when running for a long time, resulting in reduced accuracy, shortened life, and reduced reliability of the entire platform.

[0005] The existing patent with publication number CN116961272A discloses a hollow cup motor with an integrated sleeve magnet. The motor magnet and the sleeve cavity are both cylindrical, and the magnet is arranged in the sleeve cavity and connected to the sleeve as a whole. For ultra-large-caliber hollow motors, this integrated design has the disadvantages of high processing difficulty, high cost, high assembly difficulty, and easy damage. It cannot complete the signal and power transmission during the omnidirectional rotation process, does not take into account the use environment of space, and has poor reliability. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes an ultra-stable thin-wall turntable with an ultra-large aperture optical path channel for space use.

[0007] The technical solution of the present invention is:

[0008] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0009] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0010] An ultra-stable thin-walled turntable with an ultra-large-aperture optical path channel for space use adopts a "stator-rotor-stator" parallel assembly cross-sectional structure, and includes a double-row thrust angular contact ball bearing, a permanent magnet synchronous motor, an incremental inductive synchronizer, a switch Hall sensor, a position decoder, a split conductive slip ring, a load interface and a mounting flange; the permanent magnet synchronous motor, the incremental inductive synchronizer and the split conductive slip ring all use the double-row thrust angular contact ball bearing as the installation and rotation reference;

[0011] The double-row thrust angular contact ball bearing comprises a bearing inner ring and a bearing outer ring;

[0012] The permanent magnet synchronous motor includes a motor stator and a motor rotor; the permanent magnet synchronous motor has a main and backup dual winding design, and the backup winding can be quickly switched when the main winding fails to output a line fault, ensuring that the motor continues to work and avoiding sudden shutdown of the motor; the permanent magnet synchronous motor adopts a fractional slot scheme to increase the minimum number of tooth slot torque under an ideal magnetic circuit and obtain a good back electromotive force waveform.

[0013] The incremental induction synchronizer includes an induction synchronizer stator and an induction synchronizer rotor, and a magnetic shielding structure is designed to suppress interference;

[0014] The split conductive slip ring is a hollow column structure without a shaft system, and includes a conductive ring and a brush;

[0015] The motor stator is mounted on the inner ring of the bearing; the motor rotor and the outer ring of the bearing are designed as an integrated whole; axial preload is applied during assembly to prevent gaps and unloading between the inner ring of the bearing, the outer ring of the bearing and the rolling element, increase bearing stiffness, improve positioning accuracy, reduce vibration and noise, and avoid bearing damage due to vibration in a harsh dynamic environment; applying axial preload can also control the end runout and radial runout to be less than 35 μm, respectively, to realize the rotation of an ultra-stable turntable with a large-aperture optical path channel;

[0016] The induction synchronizer stator is fixed to the motor stator; the induction synchronizer rotor is fixed to the outer ring of the bearing;

[0017] The conductive ring is fixed on the outer wall of the motor rotor; the brush is fixed on the mounting flange;

[0018] The mounting flange is used to fix the inner ring of the bearing and the brushes, and to connect the ultra-stable thin-wall turntable to the spacecraft;

[0019] The position decoder can decode the output signals of the incremental inductive synchronizer and the switch Hall sensor into digital position information required by the control system.

[0020] The outer ring of the bearing is provided with an inner groove for embedding the NdFeB magnet of the motor rotor to realize the magnetic conductivity function of the magnetic yoke.

[0021] The inner ring of the bearing has a diameter greater than or equal to 1200 mm and serves as an optical path channel, and its lubrication method does not pollute the optical path.

[0022] The double-row thrust angular contact ball bearing is made of weakly magnetic bearing steel material and has the dual functions of load bearing and magnetic conductivity.

[0023] The conductive ring is made of silver-based alloy material and is fixed on the outer wall of the motor rotor; the brush is made of silver-based self-lubricating material and gold-plated beryllium bronze material and is fixed on the mounting flange.

[0024] The rated transmission power of the split conductive slip ring is greater than or equal to 2000W, and the number of transmission lines is greater than or equal to 16.

[0025] The split-type conductive slip ring friction pair material is made of self-lubricating material. After sufficient running-in and cleaning, the wear debris generated by the friction pair is mainly evenly distributed on the ring track, which greatly reduces the amount of wear debris scattered outside, avoids bringing debris to the double-row thrust angular contact ball bearing, permanent magnet synchronous motor and switch Hall sensor, and ensures the reliability of the ultra-stable thin-wall turntable.

[0026] The switch Hall sensor has an effective level range of ±0.25° and is used in combination with an incremental inductive synchronizer to achieve high-precision absolute position detection of an ultra-stable thin-wall turntable.

[0027] The load interface is used to fix and install loads such as pupil cameras.

[0028] In order to achieve micron-level output accuracy, the whole machine is assembled on a high-precision marble platform. Before and after each level of assembly, the output end is re-measured using three-coordinate measurement. After the double-row thrust angular contact ball bearing is assembled to the mounting flange, the end-to-end and radial output accuracy of the bearing outer ring is controlled within 15μm; after the motor rotor is assembled to the bearing outer ring, the output accuracy change does not exceed 2μm; the motor stator is connected to the bearing inner ring through 36 fasteners, and the coaxiality of the motor stator and the bearing inner ring is adjusted to make the air gap between the motor stator and the motor rotor 2.5±0.1mm; after the motor stator and motor rotor are installed, open-loop drive control is performed, and the end-to-end and radial output accuracy is guaranteed to be within 20μm, and the torque fluctuation does not exceed 1%; after the permanent magnet synchronous motor is assembled, the induction synchronizer rotor is assembled to the bearing outer ring, and the induction synchronizer stator is assembled to the motor stator. The coaxiality of the induction synchronizer stator and the induction synchronizer rotor is controlled within 0.1mm, and the air gap between the induction synchronizer stator and the induction synchronizer rotor is adjusted to 1±0.1mm through the silicon steel sheet. The change in the accuracy of the output end after assembly is re-measured to be no more than 1μm; the combined bracket of the split conductive slip ring is connected through the tooling cover plate, and the cylindrical surface of the tooling cover plate and the conductive ring and brush combined bracket of the split conductive slip ring are integrally processed to ensure that the coaxiality of the conductive ring and brush of the split conductive slip ring does not exceed 0.1mm. Under the positioning of the tooling cover plate, the conductive ring and brush of the split conductive slip ring are integrally installed on the outer ring of the bearing, and finally the end and radial output accuracy of the thin-walled turntable are adjusted to be no more than 35μm.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The "stator-rotor-stator" parallel assembly cross-section structure is adopted to reduce the axial length of the turntable, increase the rigidity of the large ultra-stable thin-wall turntable, and improve the output end and radial rotation accuracy of the turntable;

[0031] (2) The embedding of the permanent magnet synchronous motor’s NdFeB magnets omits the special permanent magnet synchronous motor yoke structure, realizing the structural integration design of the double-row thrust angular contact ball bearing and the permanent magnet synchronous motor, which is conducive to the lightweight and miniaturized design of the turntable;

[0032] (3) By using incremental induction synchronizers and split slip rings to reduce the number of shaft systems, the total weight of the turntable is greatly reduced, and high-power power supply and electrical signal transmission functions are realized; BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A structural diagram of an ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use provided by an embodiment of the present invention;

[0035] Figure 2 A cross-sectional view of an ultra-stable thin-walled turntable for space use with an ultra-large aperture optical path provided by an embodiment of the present invention;

[0036] In the figure: 1-1 is the inner ring of the bearing; 1-2 is the outer ring of the bearing; 2-1 is the motor stator; 2-2 is the motor rotor; 3-1 is the stator of the induction synchronizer; 3-2 is the rotor of the induction synchronizer; 4 is the switch Hall sensor; 5-1 is the conductive ring; 5-2 is the brush; 6 is the mounting flange; 7 is the load interface; 8 is the position decoder.

[0037] Specific implementation methods

[0038] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0039] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0040] A space-use ultra-stable thin-walled turntable with an ultra-large-aperture optical path channel adopts a "stator-rotor-stator" parallel assembly cross-sectional structure and comprises a double-row thrust angular contact ball bearing, a permanent magnet synchronous motor, an incremental inductive synchronizer, a switch Hall sensor (4), a position decoder (8), a split conductive slip ring, a load interface (7) and a mounting flange (6); the permanent magnet synchronous motor, the incremental inductive synchronizer and the split conductive slip ring all use the double-row thrust angular contact ball bearing as a mounting and rotation reference;

[0041] The double-row thrust angular contact ball bearing comprises a bearing inner ring (1-1) and a bearing outer ring (1-2);

[0042] The permanent magnet synchronous motor comprises a motor stator (2-1) and a motor rotor (2-2); the permanent magnet synchronous motor has a main and backup dual winding design, and the backup winding can be quickly switched when the main winding fails, so as to ensure that the motor continues to work and avoid sudden shutdown of the motor; the permanent magnet synchronous motor adopts a fractional slot scheme to increase the minimum number of tooth slot torque under an ideal magnetic circuit and obtain a good back electromotive force waveform.

[0043] The incremental induction synchronizer comprises an induction synchronizer stator (3-1) and an induction synchronizer rotor (3-2), and a magnetic shielding structure is designed to suppress interference;

[0044] The split-type conductive slip ring is a hollow columnar structure without a shaft system, and comprises a conductive ring (5-1) and a brush (5-2);

[0045] The motor stator (2-1) is mounted on the bearing inner ring (1-1); the motor rotor (2-2) and the bearing outer ring (1-2) are designed as an integrated whole; axial preload is applied during assembly to prevent gaps and unloading between the bearing inner ring (1-1), the bearing outer ring (1-2) and the rolling element, thereby increasing bearing stiffness, improving positioning accuracy, reducing vibration and noise, and avoiding bearing damage due to vibration in a harsh dynamic environment; applying axial preload can also control end runout and radial runout to be less than 35 μm, thereby realizing the rotation of an ultra-stable turntable with a large-aperture optical path channel;

[0046] The induction synchronizer stator (3-1) is fixed to the motor stator (2-1); the induction synchronizer rotor (3-2) is fixed to the bearing outer ring (1-2);

[0047] The conductive ring (5-1) is fixed on the outer wall of the bearing outer ring (1-2); the brush (5-2) is fixed on the mounting flange (6);

[0048] The mounting flange (6) is used to fix the bearing inner ring (1-1) and the brush (5-2), and to connect the ultra-stable thin-wall turntable to the spacecraft;

[0049] The position decoder (8) can decode the output signals of the incremental inductive synchronizer and the switch Hall sensor (4) into digital position information required by the control system.

[0050] The bearing outer ring (1-2) is provided with an inner groove for embedding the NdFeB magnet of the motor rotor (2-2) to realize the magnetic conductivity function of the magnetic yoke.

[0051] The bearing inner ring (1-1) has a diameter greater than or equal to 1200 mm and serves as an optical path channel, and its lubrication method does not pollute the optical path.

[0052] The double-row thrust angular contact ball bearing is made of weakly magnetic bearing steel material and has the dual functions of load bearing and magnetic conductivity.

[0053] The conductive ring (5-1) is made of a silver-based alloy material and is fixed on the outer wall of the bearing outer ring (1-2); the brush (5-2) is made of a silver-based self-lubricating material and a gold-plated beryllium bronze material and is fixed on the mounting flange (6).

[0054] The rated transmission power of the split conductive slip ring is greater than or equal to 2000W, and the number of transmission lines is greater than or equal to 16.

[0055] The friction pair material of the split conductive slip ring is self-lubricating material. After sufficient running-in and cleaning, the wear debris generated by the friction pair is mainly evenly distributed on the ring track, which greatly reduces the amount of wear debris scattered outside, avoids bringing debris to the double-row thrust angular contact ball bearing, permanent magnet synchronous motor and switch Hall sensor (4), and ensures the reliability of the ultra-stable thin-wall turntable.

[0056] The switch Hall sensor (4) has an effective level range of ±0.25° and is used in combination with an incremental inductive synchronizer to achieve high-precision absolute position detection of an ultra-stable thin-walled turntable.

[0057] The load interface (7) is used for fixedly installing loads such as pupil cameras.

[0058] In order to achieve micron-level output accuracy, the entire machine is assembled on a high-precision marble platform. Before and after each level of assembly, the output end is re-measured using three-coordinate measurement. After the double-row thrust angular contact ball bearing is assembled to the mounting flange (6), the end-to-end and radial output accuracy of the bearing outer ring (1-2) is controlled within 15 μm; after the motor rotor (2-2) is assembled to the bearing outer ring (1-2), the output accuracy variation does not exceed 2 μm; the motor stator (2-1) is connected to the bearing inner ring (1-1) through 36 fasteners, and the coaxiality of the motor stator (2-1) and the bearing inner ring (1-1) is adjusted to make the air gap between the motor stator (2-1) and the motor rotor (2-2) 2.5±0.1 mm; after the motor stator (2-1) and the motor rotor (2-2) are installed, open-loop drive control is performed, and the end-to-end and radial output accuracy is guaranteed to be within 20 μm, and the torque fluctuation does not exceed 1%; after the permanent magnet synchronous motor is assembled, the induction synchronizer rotor (3-2) is assembled to the bearing outer ring (1-2), the induction synchronizer stator (3-1) is assembled to the motor The stator (2-1) is provided with a coaxiality controllable within 0.1 mm between the induction synchronizer stator (3-1) and the induction synchronizer rotor (3-2). The air gap between the induction synchronizer stator (3-1) and the induction synchronizer rotor (3-2) is adjusted to 1±0.1 mm by silicon steel sheets. The output end precision variation after assembly is re-measured to be no more than 1 μm. The combined bracket of the split conductive slip ring is connected by a tooling cover plate. The tooling cover plate is integrally processed with the cylindrical surface of the combined bracket of the conductive ring (5-1) and the brush (5-2) of the split conductive slip ring to ensure that the coaxiality of the conductive ring (5-1) and the brush (5-2) of the split conductive slip ring is no more than 0.1 mm. Under the positioning of the tooling cover plate, the conductive ring (5-1) and the brush (5-2) of the split conductive slip ring are integrally installed on the bearing outer ring (1-2) and the mounting flange (6). Finally, the end and radial output precision of the thin-walled turntable is controlled to be no more than 35 μm.

Claims

1. An ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use, characterized in that: The "stator-rotor-stator" parallel assembly cross-sectional structure is adopted, and includes a double-row thrust angular contact ball bearing, a permanent magnet synchronous motor, an incremental inductive synchronizer, a switch Hall sensor (4), a position decoder (8), a split conductive slip ring, a load interface (7) and a mounting flange (6); The permanent magnet synchronous motor, incremental induction synchronizer and split conductive slip ring are all installed and rotated based on double row thrust angular contact ball bearings; The double-row thrust angular contact ball bearing comprises a bearing inner ring (1-1) and a bearing outer ring (1-2); The permanent magnet synchronous motor comprises a motor stator (2-1) and a motor rotor (2-2); The incremental induction synchronizer is designed with a magnetic shielding structure to suppress interference, and comprises an induction synchronizer stator (3-1) and an induction synchronizer rotor (3-2); The split-type conductive slip ring is a hollow columnar structure without a shaft system, and comprises a conductive ring (5-1) and a brush (5-2); The motor stator (2-1) is mounted on the bearing inner ring (1-1); the motor rotor (2-2) and the bearing outer ring (1-2) are designed in an integrated manner; The induction synchronizer stator (3-1) is fixed to the motor stator (2-1); the induction synchronizer rotor (3-2) is fixed to the bearing outer ring (1-2); The conductive ring (5-1) is fixed on the outer wall of the motor rotor (2-2); the brush (5-2) is fixed on the mounting flange (6); The mounting flange (6) is used to fix the bearing inner ring (1-1) and the brush (5-2), and to connect the ultra-stable thin-wall turntable to the spacecraft; The position decoder (8) can decode the output signals of the incremental inductive synchronizer and the switch Hall sensor (4) into digital position information required by the control system.

2. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The permanent magnet synchronous motor has a main and backup dual winding design, and the backup winding can be quickly switched when the main winding fails, ensuring that the motor continues to work and avoiding sudden shutdown of the motor.

3. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The permanent magnet synchronous motor adopts a fractional slot solution.

4. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The bearing outer ring (1-2) is provided with an inner groove for embedding the NdFeB magnet of the motor rotor (2-2) to realize the magnetic conductivity function of the magnetic yoke.

5. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The conductive ring (5-1) is made of a silver-based alloy material and is fixed on the outer wall of the motor rotor (2-2); the brush (5-2) is made of a silver-based self-lubricating material and a gold-plated beryllium bronze material and is fixed on the mounting flange (6).

6. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The double-row thrust angular contact ball bearing is made of weakly magnetic bearing steel material and has the dual functions of load bearing and magnetic conductivity.

7. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The friction pair material of the split conductive slip ring is made of self-lubricating material. After running-in and cleaning, the wear debris generated by the friction pair is evenly distributed on the ring track, reducing the amount of wear debris scattered outside and ensuring the reliability of the ultra-stable thin-wall turntable.

8. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The switch Hall sensor (4) has an effective level range of ±0.25° and is used in combination with an incremental inductive synchronizer to achieve high-precision absolute position detection of an ultra-stable thin-walled turntable.

9. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The diameter of the bearing inner ring (1-1) is greater than or equal to 1200 mm.

10. The ultra-stable thin-walled turntable with an ultra-large aperture optical path for space use as claimed in claim 1, characterized in that: The rated transmission power of the split conductive slip ring is greater than or equal to 2000W, and the number of transmission lines is greater than or equal to 16.

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