CN111834754A - Actuator for main reflecting surface active control system of large radio telescope - Google Patents
Actuator for main reflecting surface active control system of large radio telescope Download PDFInfo
- Publication number
- CN111834754A CN111834754A CN202010574267.7A CN202010574267A CN111834754A CN 111834754 A CN111834754 A CN 111834754A CN 202010574267 A CN202010574267 A CN 202010574267A CN 111834754 A CN111834754 A CN 111834754A
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- transmission shaft
- gear
- actuator
- harmonic reducer
- reflecting surface
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- 230000005540 biological transmission Effects 0.000 claims abstract description 63
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 46
- 230000001681 protective effect Effects 0.000 claims description 9
- 230000033001 locomotion Effects 0.000 claims description 6
- 238000012423 maintenance Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 6
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/14—Reflecting surfaces; Equivalent structures
- H01Q15/147—Reflecting surfaces; Equivalent structures provided with means for controlling or monitoring the shape of the reflecting surface
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
Abstract
The invention discloses an actuator for a main reflecting surface active control system of a large radio telescope, which comprises a motor and a harmonic reducer which are connected through a transmission mechanism, wherein the harmonic reducer is connected with an electric cylinder mechanism. The actuator for the active control system of the main reflecting surface of the large radio telescope, disclosed by the invention, not only is the bearing capacity of the actuator improved and the problem of convenience in later maintenance solved, but also the pose adjustment and the precision control of the main reflecting surface of the large radio telescope can be realized, and the requirement of a high-precision active control system is met.
Description
Technical Field
The invention belongs to the technical field of precision machinery, and relates to an actuator for a main reflecting surface active control system of a large radio telescope.
Background
Since China added a line for exploring space, research on radio telescopes began. The aperture of the radio telescope and the used observation wavelength determine the limit resolution, the larger the aperture, the shorter the wavelength, the higher the resolution of the radio telescope, and therefore, the aperture of the radio telescope is larger and larger for the scientific development requirement.
When the telescope is observed, the aperture is increased, the influence of gravity and external natural conditions is obvious, the antenna panel is difficult to keep an ideal position all the time, and the resolution precision of the radio telescope is seriously influenced.
The actuator is a pose adjusting mechanism of the telescope main reflecting surface. Early actuators were of the electro-hydraulic motor type and the motor cylinder type, and with the development of technology, later variable frequency driven actuators and hydraulic actuators appeared. The device has the greatest characteristics of simple structure, low precision and easy operation.
In order to meet the requirements of scientific research, the surface type of the reflecting surface unit is changed by adopting an actuator. The main reflecting surface is divided into a plurality of sub-panels, and each sub-panel is driven by the actuator to make micro displacement, so that the deformation of the main reflecting surface is compensated, and the celestial body is tracked. However, the large radio telescope is heavy, the working environment is severe, and a large number of actuators are needed, so that the problems of serious damage inside the actuators, difficulty in repair and the like are caused, and the precision of the main reflecting surface is further influenced, so that the traditional main reflecting surface pose adjusting mechanism cannot meet the existing requirements.
Disclosure of Invention
The invention aims to provide an actuator for an active control system of a main reflecting surface of a large radio telescope, which solves the problems of large quantity and poor fine adjustment effect of the actuator on the main reflecting surface of the large radio telescope in the prior art.
The invention adopts the technical scheme that the actuator for the main reflecting surface active control system of the large radio telescope comprises a motor and a harmonic reducer which are connected through a transmission mechanism, wherein the harmonic reducer is connected with an electric cylinder mechanism.
The present invention is also characterized in that,
the transmission mechanism comprises a transmission shaft A, one end of the transmission shaft A is connected with the motor, a brake is arranged on the transmission shaft A, a helical gear A is coaxially fixed on the transmission shaft A, a helical gear B is meshed with the helical gear A, a transmission shaft B is coaxially fixed on the helical gear B, and the transmission shaft A and the transmission shaft B are arranged in parallel.
The transmission mechanism further comprises a gear box, the brake is located on a box cover of the gear box, the helical gear A and the helical gear B are located in the gear box, two grooves are formed in the bottom of the gear box, the other end of the transmission shaft A and the bottom end of the transmission shaft B are located in the two grooves of the gear box respectively, a bearing A and a bearing B are arranged at the other end of the transmission shaft A and the bottom end of the transmission shaft B respectively, a bearing C is arranged on the transmission shaft B, and the bearing C is located between the transmission.
The motor is a stepping motor, a motor protective cover is covered outside the motor and fixed on a box cover of the gear box, one end of a transmission shaft A extends into the motor protective cover and is connected with the motor through a coupler, a motor frame is arranged on the brake, and the motor is fixed on the motor frame.
The harmonic reducer comprises a wave generator, a flexible gear, a rigid gear and a flexible bearing, wherein the wave generator is coaxially connected with the transmission shaft B, the wave generator is in supporting connection with the flexible gear through the flexible bearing, the flexible gear is arranged in the rigid gear and meshed with the rigid gear, and the rigid gear is coaxially connected with a harmonic reducer output shaft.
A harmonic reducer support frame is fixed on the gear box, a harmonic reducer support is fixed on the harmonic reducer support frame, the harmonic reducer is located on the harmonic reducer support, and a positioning sleeve is arranged between the harmonic reducer support frame and the transmission shaft B.
The electric cylinder mechanism comprises an electric cylinder shell, a rigid guide sleeve is sleeved outside the electric cylinder shell, a pull plate is fixed on the rigid guide sleeve, a pull rod is fixedly connected onto the pull plate, a lead screw is arranged in the electric cylinder shell, a lead screw nut is arranged on the lead screw, the lead screw nut does vertical linear motion along the lead screw, and the lead screw is connected with an output shaft of the harmonic reducer.
And a bearing D and a bearing E are respectively arranged at the connecting end of the screw rod and the output shaft of the harmonic reducer, and the bearing D and the bearing E are both positioned between the screw rod and the electric cylinder shell.
A sliding bearing is arranged between the rigid guide sleeve and the electric cylinder shell.
The invention has the beneficial effects that:
the actuator for the active control system of the main reflecting surface of the large radio telescope not only improves the bearing capacity of the actuator and solves the problems of convenient later maintenance, but also can realize the pose adjustment and the precision control of the main reflecting surface of the large radio telescope and meet the requirement of a high-precision active control system; the parallel helical gears are arranged in a transmission system, so that the bearing capacity is improved; the problems of load and working time in a severe working environment can be solved, and the bevel gear is arranged close to the bottom of the gear box, so that the assembly, disassembly and later maintenance are convenient; the harmonic reducer is simple in structure, convenient to assemble and disassemble and capable of achieving a high reduction ratio; the actuator is sealed, and the conditions of exposure and corrosion of internal parts are reduced; the actuator of the invention can ensure that the stepping motor has the characteristics of large load capacity, high positioning precision, high transmission efficiency, reliable operation and the like when working normally.
Drawings
FIG. 1 is a schematic structural diagram of an actuator for an active control system of a main reflecting surface of a large radio telescope according to the present invention;
FIG. 2 is a schematic structural diagram of a gearbox body in an actuator of an active control system for a main reflecting surface of a large radio telescope, according to the present invention;
FIG. 3 is a schematic structural diagram of a gearbox cover in an actuator of an active control system for a main reflector of a large radio telescope according to the present invention;
FIG. 4 is a schematic structural diagram of a motor shield in an actuator for an active control system of a main reflector of a large radio telescope according to the present invention;
FIG. 5 is a schematic structural diagram of a harmonic reducer in an actuator of an active control system for a main reflecting surface of a large radio telescope according to the present invention;
FIG. 6 is a schematic structural diagram of a harmonic reducer support in an actuator of an active control system for a main reflector of a large radio telescope according to the present invention;
FIG. 7 is a cross-sectional view of a positioning sleeve in an actuator for an active control system of a main reflecting surface of a large radio telescope according to the present invention.
In the figure, 1, a motor protective cover, 2, a motor, 3, a coupler, 4, a motor mounting frame, 5, a brake, 6, a transmission shaft A, 7, a gear box body, 8, a bevel gear A, 9, a bearing A, 10, a bearing B, 11, a bevel gear B, 12, a transmission shaft B, 13, a bearing C, 14, a gear box cover, 15, a harmonic reducer support frame, 16, a flexible gear, 17, a harmonic reducer positioning sleeve, 18, a wave generator, 19, a flexible bearing, 20, a rigid gear, 21, a harmonic reducer support, 22, a harmonic reducer output shaft, 23, a bearing D, 24, a bearing E, 25, a screw rod, 26, a sliding bearing, 27, a pull plate, 28, a screw rod nut, 29 an electric cylinder shell, 30, a rigid guide sleeve and 31 are arranged.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
The invention relates to an actuator for a main reflecting surface active control system of a large radio telescope, which comprises a motor 2 and a harmonic reducer connected through a transmission mechanism, wherein the harmonic reducer is connected with an electric cylinder mechanism, as shown in figure 1.
The transmission mechanism comprises a transmission shaft A6 with one end connected with the motor 2, a brake 5 is arranged on the transmission shaft A6, a helical gear A8 is coaxially fixed on the transmission shaft A6, a helical gear B11 is meshed with the helical gear A8, a transmission shaft B12 is coaxially fixed on the helical gear B11, and the transmission shaft A6 and the transmission shaft B12 are arranged in parallel.
The transmission mechanism further comprises a gear box 7, a box body and a box cover 14 of the gear box 7 are respectively shown in fig. 2 and 3, a brake 5 is located on the box cover 14 of the gear box 7, a bevel gear a8 and a bevel gear B11 are located in the gear box 7, the bottom of the gear box 7 is provided with two grooves, the other end of a transmission shaft a6 and the bottom end of a transmission shaft B12 are respectively located in the two grooves of the gear box 7, the other end of the transmission shaft a6 and the bottom end of a transmission shaft B12 are respectively provided with a bearing a9 and a bearing B10, a bearing C13 is arranged on the transmission shaft B12, and a bearing C13 is.
The motor 2 is a stepping motor, the motor protective cover 1 is covered outside the motor 2, as shown in fig. 4, the motor protective cover 1 is fixed on the box cover 14 of the gear box 7, one end of the transmission shaft A6 extends into the motor protective cover 1 and is connected with the motor 2 through the coupler 3, the brake 5 is provided with the motor frame 4, and the motor 2 is fixed on the motor frame 4.
As shown in fig. 5, the harmonic reducer comprises a wave generator 18, a flexible gear 16, a rigid gear 20 and a flexible bearing 19, wherein the wave generator 18 is coaxially connected with a transmission shaft B12, the wave generator 18 is in supporting connection with the flexible gear 16 through the flexible bearing 19, the flexible gear 16 is arranged in the rigid gear 20, the flexible gear 16 is meshed with the rigid gear 20, and the rigid gear 20 is coaxially connected with a harmonic reducer output shaft 22.
A harmonic reducer support frame 15 shown in fig. 6 is fixed on the gear box 7, a harmonic reducer support 21 is fixed on the harmonic reducer support frame 15, the harmonic reducer is located on the harmonic reducer support frame 21, and a positioning sleeve 17 shown in fig. 7 is arranged between the harmonic reducer support frame 15 and the transmission shaft B12.
The electric cylinder mechanism comprises an electric cylinder shell 29, a rigid guide sleeve 30 is sleeved outside the electric cylinder shell 29, a sliding bearing 26 is arranged between the rigid guide sleeve 30 and the electric cylinder shell 29, a pulling plate 27 is fixed on the rigid guide sleeve 30, a pulling rod 31 is fixedly connected onto the pulling plate 27, a screw rod 25 is arranged in the electric cylinder shell 29, a screw rod nut 28 is arranged on the screw rod 25, the screw rod nut 28 does up-and-down linear motion along the screw rod 25, the screw rod 25 is connected with a harmonic reducer output shaft 22, a bearing D23 and a bearing E24 are respectively arranged at the connecting end of the screw rod 25 and the harmonic reducer output shaft 22, and the bearing D23 and the bearing E24 are both positioned between the screw rod 25 and.
The working process of the actuator for the main reflecting surface active control system of the large radio telescope is as follows:
the brake 5 is electrified and loosens the transmission shaft A6 in a braking state, the motor 2 is electrified and drives the transmission shaft A6 to operate through the coupler 3, so that power is transmitted to the helical gear A8, then the helical gear A8 transmits the power to the helical gear B11, and the helical gear B11 drives the transmission shaft B12 to operate to output the power;
the transmission shaft B12 drives the wave generator 18 to rotate, so that the meshing state of the flexible gear 16 and the rigid gear 20 is changed continuously, the flexible gear 16 rotates slowly along the wave generator 18 relative to the rigid gear 20, and the speed reduction purpose is finally achieved;
the harmonic reducer output shaft 22 transmits power to the lead screw 25 through a key connection mode, the lead screw 25 rotates under the support of bearings D23 and E24 and drives the lead screw nut 28 to move, and the lead screw nut 28 is restrained by the slide way and can only do reciprocating linear motion. When the screw nut 28 moves, the rigid guide sleeve 30 is driven to do reciprocating linear motion along the electric cylinder shell 29, and because the sliding bearing 26 is arranged in the rigid guide sleeve 30, the abrasion is small; the movement of the rigid guide sleeve 30 drives the pulling plate 27 and the pulling rod 31 to move, so that the stability of the adjustment work of the main reflecting surface is ensured, and the pose adjustment and the precision control of the antenna reflecting surface are realized.
Claims (9)
1. The actuator for the active control system of the main reflecting surface of the large radio telescope is characterized by comprising a motor (2) and a harmonic reducer which are connected through a transmission mechanism, wherein the harmonic reducer is connected with an electric cylinder mechanism.
2. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope according to claim 1, wherein the transmission mechanism comprises a transmission shaft A (6) with one end connected with the motor (2), the transmission shaft A (6) is provided with a brake (5), the transmission shaft A (6) is coaxially fixed with a bevel gear A (8), the bevel gear A (8) is engaged with a bevel gear B (11), the bevel gear B (11) is coaxially fixed with a transmission shaft B (12), and the transmission shaft A (6) and the transmission shaft B (12) are arranged in parallel.
3. An actuator for an active control system of a main reflecting surface of a large radio telescope according to claim 2, characterized in that the transmission mechanism also comprises a gear box (7), the brake (5) is positioned on a box cover (14) of the gear box (7), the bevel gear A (8) and the bevel gear B (11) are positioned in the gear box (7), the bottom of the gear box (7) is provided with two grooves, the other end of the transmission shaft A (6) and the bottom end of the transmission shaft B (12) are respectively positioned in the two grooves of the gear box (7), and the other end of the transmission shaft A (6) and the bottom end of the transmission shaft B (12) are respectively provided with a bearing A (9) and a bearing B (10), the transmission shaft B (12) is provided with a bearing C (13), and the bearing C (13) is positioned between the transmission shaft B (12) and a box cover (14) of the gear box (7).
4. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope according to claim 2, wherein the motor (2) is a stepping motor, the motor (2) is externally covered with a motor protective cover (1), the motor protective cover (1) is fixed on a box cover (14) of the gear box (7), one end of the transmission shaft A (6) extends into the motor protective cover (1) and is connected with the motor (2) through a coupler (3), the brake (5) is provided with a motor frame (4), and the motor (2) is fixed on the motor frame (4).
5. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope is characterized in that the harmonic reducer comprises a wave generator (18), a flexible gear (16), a rigid gear (20) and a flexible bearing (19), wherein the wave generator (18) is coaxially connected with the transmission shaft B (12), the wave generator (18) is in supporting connection with the flexible gear (16) through the flexible bearing (19), the flexible gear (16) is arranged in the rigid gear (20), the flexible gear (16) is meshed with the rigid gear (20), and the rigid gear (20) is coaxially connected with a harmonic reducer output shaft (22).
6. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope according to claim 5, wherein a harmonic reducer support frame (15) is fixed on the gear box (7), a harmonic reducer support frame (21) is fixed on the harmonic reducer support frame (15), the harmonic reducer is located on the harmonic reducer support frame (21), and a positioning sleeve (17) is arranged between the harmonic reducer support frame (15) and the transmission shaft B (12).
7. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope according to claim 5, wherein the electric cylinder mechanism comprises an electric cylinder shell (29), a rigid guide sleeve (30) is sleeved outside the electric cylinder shell (29), a pulling plate (27) is fixed on the rigid guide sleeve (30), a pulling rod (31) is fixedly connected to the pulling plate (27), a lead screw (25) is arranged in the electric cylinder shell (29), a lead screw nut (28) is arranged on the lead screw (25), the lead screw nut (28) makes up-and-down linear motion along the lead screw (25), and the lead screw (25) is connected with an output shaft (22) of the harmonic reducer.
8. The actuator for the active control system of the main reflecting surface of the large-scale radio telescope according to claim 7, characterized in that the connecting ends of the screw rod (25) and the harmonic reducer output shaft (22) are respectively provided with a bearing D (23) and a bearing E (24), and the bearing D (23) and the bearing E (24) are both positioned between the screw rod (25) and the electric cylinder shell (29).
9. Actuator for an active control system of a main reflecting surface of a large radio telescope according to claim 7, characterized in that a sliding bearing (26) is arranged between the rigid guide sleeve (30) and the electric cylinder housing (29).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010574267.7A CN111834754A (en) | 2020-06-22 | 2020-06-22 | Actuator for main reflecting surface active control system of large radio telescope |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010574267.7A CN111834754A (en) | 2020-06-22 | 2020-06-22 | Actuator for main reflecting surface active control system of large radio telescope |
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| Publication Number | Publication Date |
|---|---|
| CN111834754A true CN111834754A (en) | 2020-10-27 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010574267.7A Pending CN111834754A (en) | 2020-06-22 | 2020-06-22 | Actuator for main reflecting surface active control system of large radio telescope |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102593608A (en) * | 2012-03-09 | 2012-07-18 | 上海交通大学 | Electric actuator for actively adjusting main reflection face of large-size radio telescope |
| US20130276575A1 (en) * | 2010-10-07 | 2013-10-24 | Tq-Systems Gmbh | Gear, motor-gear unit, vehicle, generator with a gear, and force transmitting element |
| CN104343924A (en) * | 2014-10-13 | 2015-02-11 | 上海交通大学 | Four-axis actuator |
| CN105158895A (en) * | 2015-10-13 | 2015-12-16 | 中国科学院国家天文台南京天文光学技术研究所 | Micromovement actuator used for adjusting mirror surface position of astronomical telescope |
| CN205036819U (en) * | 2015-09-23 | 2016-02-17 | 浙江来福谐波传动股份有限公司 | Compact structure's duplex bearing harmonic speed reducer ware |
| CN105697663A (en) * | 2016-03-22 | 2016-06-22 | 广东工业大学 | Mechanical device for applying harmonic reducer to bothway transmission |
-
2020
- 2020-06-22 CN CN202010574267.7A patent/CN111834754A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130276575A1 (en) * | 2010-10-07 | 2013-10-24 | Tq-Systems Gmbh | Gear, motor-gear unit, vehicle, generator with a gear, and force transmitting element |
| CN102593608A (en) * | 2012-03-09 | 2012-07-18 | 上海交通大学 | Electric actuator for actively adjusting main reflection face of large-size radio telescope |
| CN104343924A (en) * | 2014-10-13 | 2015-02-11 | 上海交通大学 | Four-axis actuator |
| CN205036819U (en) * | 2015-09-23 | 2016-02-17 | 浙江来福谐波传动股份有限公司 | Compact structure's duplex bearing harmonic speed reducer ware |
| CN105158895A (en) * | 2015-10-13 | 2015-12-16 | 中国科学院国家天文台南京天文光学技术研究所 | Micromovement actuator used for adjusting mirror surface position of astronomical telescope |
| CN105697663A (en) * | 2016-03-22 | 2016-06-22 | 广东工业大学 | Mechanical device for applying harmonic reducer to bothway transmission |
Non-Patent Citations (2)
| Title |
|---|
| 岳立新编: "《机械基础》", 31 January 2009, 电子科技大学出版社 * |
| 郑树琴主编: "《机械原理》", 31 July 2016, 国防工业出版社 * |
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Application publication date: 20201027 |