Transmission mechanism for photoelectric rotary table

Abstract

The invention discloses a transmission mechanism for a photoelectric rotary table. The transmission mechanism comprises a motor assembly; the speed reducer assembly comprises a feedback shaft and an inner gear ring shell; a plurality of planetary gear sets are arranged in the inner gear ring shell, and each planetary gear set comprises a sun gear, a planet gear and a rotating stand; the sun gear of the first-stage planetary gear set is connected with the rotor, the rotating stand of the previous planetary gear set is connected with the sun gear of the next planetary gear set through a spline pair, the rotating stand of the last-stage planetary gear set is connected with the feedback shaft, all the sun gears are arranged on the outer side of the feedback shaft in a sleeving mode, and a first encoder is installed on the feedback shaft; the brake assembly is provided with a brake with a friction disc, the friction disc is connected with a brake sleeve rotating synchronously, the brake sleeve is connected with the rotor, and a second encoder is installed on the brake sleeve; the problems of large size, serious vibration coupling, control lag and the like caused by insufficient positioning precision, low transmission efficiency and low integration degree of a transmission mechanism of an existing photoelectric rotary table are solved.

Description

Technical Field

[0001] This invention relates to the field of photoelectric turntable technology, specifically to a transmission mechanism for a photoelectric turntable. Background Technology

[0002] An optoelectronic turntable is a device that integrates optical imaging equipment (such as visible light cameras, infrared thermal imagers, and laser rangefinders) and a precision transmission mechanism. It is primarily used for tracking, observing, aiming, or measuring targets. Through a high-precision servo control system, it achieves rapid and stable azimuth and pitch rotation, and is widely used in military, security, aerospace, and scientific research fields. These applications rely on the high performance of the transmission mechanism, whose technical specifications directly determine the overall efficiency of the optoelectronic turntable.

[0003] Existing photoelectric rotary table transmission mechanisms suffer from numerous technical bottlenecks: traditional gear drives employ a discrete layout, and the cumulative tooth backlash generated by multi-stage gear meshing leads to positioning errors exceeding 0.1°, failing to meet high-precision tracking requirements. While worm gear drives can achieve self-locking, their transmission efficiency is generally below 70%, posing a significant limitation in energy-constrained fields such as aerospace. Belt and chain drives, due to issues such as elastic slippage, chain polygonal effects, and wear elongation, not only exhibit poor positioning accuracy but also suffer from high accuracy decay over long-term operation, resulting in significant positioning lag and error fluctuations.

[0004] In terms of structural design, existing optoelectronic turntables mostly employ a split-assembly for their transmission mechanisms. Core components such as motors, reducers, and brakes are combined through complex connectors, resulting in a bulky overall size and limited hollow aperture (typically less than 50mm), which fails to meet the requirements for center wiring and optical path integration in optoelectronic turntables. Furthermore, the split structure exhibits significant vibration coupling issues. The high-frequency vibrations generated by the motor, after rigid transmission, can cause blurred imaging of the optoelectronic payload, which is particularly noticeable in high-magnification observation scenarios. In terms of control accuracy, existing mechanisms mostly use single encoder feedback, which can only monitor the motion state of the motor end and cannot truly reflect the actual position of the load end, resulting in a control lag error of 0.05°-0.1°. In fast dynamic tracking scenarios, this lag can cause the target to miss, especially when tracking high-speed targets.

[0005] Therefore, the development of new transmission mechanisms with high efficiency, high integration, and high control precision has become an urgent need for the development of optoelectronic turntable technology. Summary of the Invention

[0006] The purpose of this invention is to provide a transmission mechanism for an optoelectronic turntable, which aims to improve the problems of insufficient positioning accuracy, low transmission efficiency, large size due to low integration, severe vibration coupling, and control lag in the existing transmission mechanisms of optoelectronic turntables.

[0007] The present invention is implemented as follows: a transmission mechanism for an optoelectronic turntable, comprising: The motor assembly includes a motor housing, a stator, and a rotor disposed within the motor housing; The reducer assembly includes a hollow feedback shaft and an internal gear ring housing with an internal gear ring on its inner wall. The internal gear ring housing is connected to and communicates with a motor housing. Multiple sets of planetary gears are arranged sequentially along the axial direction of the feedback shaft within the internal gear ring housing. Each planetary gear set includes a sun gear, planet gears, and a carrier. The planet gears of each planetary gear set are meshed with the internal gear ring housing. The sun gear of the first-stage planetary gear set is connected to the rotor. The carrier of the preceding planetary gear set is connected to the sun gear of the following planetary gear set via a spline pair. The carrier of the last-stage planetary gear set is connected to the feedback shaft, and each sun gear is sleeved on the outside of the feedback shaft. A first encoder is mounted on the feedback shaft. A brake assembly includes a brake housing connected to and communicating with a motor housing; a brake with a friction disc is disposed in the brake housing, the friction disc is connected to a synchronously rotating brake sleeve, the brake sleeve is connected to a rotor, and a second encoder is mounted on the brake sleeve.

[0008] Furthermore, the motor housing is provided with a first annular flange and a second annular flange at both ends, and the outer diameter of the first annular flange and the second annular flange is larger than the outer diameter of the motor housing body. The motor housing is connected to the internal gear ring housing through the first annular flange and to the brake housing through the second annular flange.

[0009] Furthermore, the reducer assembly includes three planetary gear sets, namely K1 planetary gear set, K2 planetary gear set and K3 planetary gear set. The K1 sun gear of the K1 planetary gear set is connected to the rotor. The K2 sun gear of the K2 planetary gear set is connected to the K1 carrier of the K1 planetary gear set through a spline joint. The K3 sun gear of the K3 planetary gear set is connected to the K2 carrier of the K2 planetary gear set through a spline joint.

[0010] Furthermore, the K1 and K2 rotating frames have the same structure, both including a frame with a central through hole for the feedback shaft to pass through. An internal spline groove is provided on one side of the frame, and external spline structures adapted to the internal spline grooves are correspondingly provided on one side of the K2 and K3 sun gears. The external spline structure of the K2 sun gear meshes with the internal spline groove of the K1 rotating frame, and the external spline structure of the K3 sun gear meshes with the internal spline groove of the K2 rotating frame. At least three planetary shafts are evenly arranged along the circumferential direction on the frame, and each planetary shaft is equipped with a planetary gear. The frame and the planetary gears are connected by pins, and the planetary gears are connected to the planetary shafts by needle roller bearings. Oil passages leading to the needle roller bearings are provided on the planetary shafts, and oil nozzles are provided in the oil passages.

[0011] Furthermore, the K3 carrier of the K3 planetary gear set includes a frame for mounting the planetary gears within the set, and a support connection portion is provided on the side of the frame away from the K2 carrier. The end of the support connection portion is provided with a connecting thread for connecting to the photoelectric turntable. Multiple connecting thread holes are evenly arranged along the circumferential direction of the end of the support connection portion. A first annular groove is provided on the end of the support connection portion inside each connecting thread hole. Multiple first mounting thread holes are evenly arranged along the circumferential direction on the bottom wall of the first annular groove. A second connecting flange is provided at the end of the feedback shaft connected to the K3 carrier. The second connecting flange is connected to the support connection portion by a second bolt, and the threaded part of the second bolt is screwed into the first mounting thread hole.

[0012] Furthermore, an end cap is connected to the end of the internal gear ring housing away from the motor housing via a third bolt. The end cap is generally annular, and the support connection of the K3 frame passes through the end cap. The end cap has an inner extending annular portion, the outer wall of which is in contact with the inner wall of the internal gear ring housing, and a sealing ring is provided between them. A fifth bearing mounting portion is provided on the support connection portion, and a crossed roller bearing is mounted on the fifth bearing mounting portion. The inner and outer rings of the crossed roller bearing are in contact with the inner walls of the fifth bearing mounting portion and the inner extending annular portion, respectively.

[0013] Furthermore, the feedback shaft passes through the brake sleeve and the friction disc. The brake sleeve is provided with an external brake spline at the end away from the rotor, and the friction disc is provided with an internal brake spline that matches the external brake spline on its inner wall. The external brake spline is inserted into the internal brake spline to achieve synchronous rotation of the brake sleeve and the friction disc.

[0014] Furthermore, a bushing is provided on the inner wall of the brake sleeve, and the feedback shaft passes through the bushing; the bushing is interference-fitted with the inner wall of the brake sleeve and clearance-fitted with the outer wall of the feedback shaft; a limiting sleeve is detachably installed at the end of the brake sleeve connected to the rotor, and the feedback shaft passes through the limiting sleeve, with a certain gap between the feedback shaft and the inner wall of the limiting sleeve; a limiting step is provided on the inner wall of the brake sleeve on the side of the bushing away from the limiting sleeve, and the limiting sleeve is connected to the bushing to press the bushing tightly onto the limiting step; multiple grease grooves are evenly provided on the inner wall of the bushing along its circumference.

[0015] Furthermore, a rear cover is detachably connected to the end of the brake housing away from the motor housing, and the rear cover is provided with a through hole for the feedback shaft to pass through; a first circular ring connecting part and a second circular ring connecting part are provided on the inner wall of the brake housing, the brake is connected to the first circular ring connecting part, and a partition is installed on the second circular ring connecting part; the first encoder has a first reading head, the second encoder has a second reading head, and both the first reading head and the second reading head are installed on the partition.

[0016] Furthermore, a motor brake socket and an encoder socket are installed on the rear cover. The motor brake socket is electrically connected to the motor assembly and the brake, and the encoder socket is electrically connected to the first encoder and the second encoder.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention significantly improves transmission accuracy and efficiency by integrating the motor assembly, reducer assembly, and brake assembly into a single, interconnected structure, combined with the spline transmission of a multi-stage planetary gear set. Specifically, the internal gear ring housing is connected and communicates with the motor housing, and the brake housing is also connected and communicates with the motor housing, forming a compact power transmission channel. In the reducer assembly, the sun gear of the first-stage planetary gear set is connected to the rotor, and the first set of carriers meshes with the external spline structure of the second set of sun gears through an internal spline groove. This rigid spline fit reduces the accumulated tooth backlash of traditional discrete gears. Simultaneously, the meshing transmission efficiency of the planetary gear set is far higher than that of worm gear drives, overcoming the shortcoming of traditional transmission efficiencies below 70%, making it more suitable for energy-constrained scenarios.

[0018] 2. This invention optimizes spatial layout and reduces the impact of vibration coupling through an integrated shell design and hollow feedback shaft structure. The interconnected assembly of the motor shell, internal gear ring shell, and brake shell reduces redundant connecting parts in a split structure, thus reducing the overall volume. The hollow feedback shaft runs through each sun gear and the rotating frame, meeting the requirements for central wiring and optical path integration of the photoelectric turntable, breaking through the limitation of traditional mechanisms with a hollow aperture of less than 50mm, reaching 80mm. In addition, the integrated structure shortens the vibration transmission path, and the stable support of the needle roller bearings between the planetary gears and planetary shafts reduces the interference of high-frequency motor vibration on optical imaging equipment, avoiding imaging blurring problems during high-magnification observation.

[0019] 3. This invention improves control accuracy and shortens dynamic response lag through a dual-encoder feedback and braking linkage design. The first encoder on the feedback shaft monitors the actual output position of the final stage rotor, while the second encoder on the brake sleeve monitors the input motion state of the rotor. The dual encoder signals are transmitted to the control system via encoder sockets, achieving a closed-loop comparison of "input-output," solving the problem that traditional single encoders cannot reflect the true position of the load end and keeping control lag error within a lower range. Simultaneously, the friction disc of the brake is linked to the external spline of the brake sleeve via the internal spline, enabling rapid response to braking demands and preventing target misses during rapid tracking. Attached Figure Description

[0020] Figures 1-3 This is a cross-sectional view of the transmission mechanism for an optoelectronic turntable provided in the embodiment, wherein, Figure 1 Number the entire structure. Figure 2 The main task is to label the reducer components. Figure 3 The group needs to label the motor assembly and the brake assembly; Figure 4 This is a cross-sectional view of the feedback shaft and the first encoder mounted on it; Figure 5 This is a cross-sectional view showing the connection between the K2 sun gear and the K1 planetary gear set with the K1 sun gear removed; Figure 6 This is a three-dimensional structural diagram of the connection point between the K3 sun gear and the K2 planetary gear set (with the K2 sun gear removed); Figure 7 This is a three-dimensional structural diagram of the K1 sun gear; Figure 8 This is a three-dimensional structural diagram of the K3 rotating frame; Figure 9 This is a cross-sectional view of the end cap; Figure 10 This is a three-dimensional structural diagram of the connection point between the brake sleeve and the brake assembly; Figure 11 These are cross-sectional views and A-direction views showing the location of the brake assembly in the transmission mechanism; Figure 12 This is a three-dimensional structural diagram of the brake sleeve when a limit sleeve and a bushing are installed on it. Figure 13 This is a cross-sectional view of the brake sleeve when the limit sleeve and bushing are installed on it. Figure 14 This is a schematic diagram of the structure of a brake provided in the embodiment; Figure 15 This is a power transmission route diagram of the transmission mechanism for an optoelectronic turntable provided in the embodiment.

[0021] In the diagram: 1. Reducer assembly; 2. Motor assembly; 3. Brake assembly; 4. Connecting bolt; 5. Connecting bolt; 6. Feedback shaft; 7. K3 frame; 8. Crossed roller bearing; 9. End cover; 10. Internal gear ring housing; 11. K3 planetary gear set; 12. K2 planetary gear set; 13. K1 planetary gear set; 14. First encoder; 15. K1 sun gear; 16. K2 sun gear; 17. K3 sun gear; 18. Second bolt; 19. Fastening screw; 20. Fourth bearing; 21. 1. External gear ring structure; 22. Third bolt; 23. K2 frame; 24. External spline structure; 25. Internal spline groove; 26. First connecting flange; 27. Third bearing; 28. Pin; 29. ​​Planetary gear; 30. K1 frame; 31. Planetary shaft; 32. Oil nozzle; 33. Oil passage; 34. Needle roller bearing; 35. First bearing; 36. Motor housing; 37. Stator; 38. Rotor; 39. Second encoder; 40. Bushing; 41. Sixth bearing; 42. Brake sleeve; 43. Sixth bolt ; 44. First bolt; 45. Friction disc; 46. Brake internal spline; 47. Brake external spline; 48. Brake housing; 49. Eighth bolt; 50. Brake; 51. Partition plate; 52. Rear cover; 53. Ninth bolt; 54. First reading head; 55. Second reading head; 56. Tenth bolt; 57. Ninth bolt; 58. Fifth bolt; 59. Motor brake socket; 60. Eleventh bolt; 61. Encoder socket; 62. Support connection part; 63. Fifth bearing mounting part; 64. 65. Circular groove; 66. First mounting threaded hole; 67. Connecting threaded hole; 68. Inner extending circular ring portion; 69. Oil seal mounting portion; 70. First snap ring groove; 71. Second mounting threaded hole; 72. Limiting sleeve; 73. Limiting step; 74. Fourth connecting flange; 75. Seventh bolt; 76. Grease groove; 77. First bearing mounting portion; 78. Second bearing mounting portion; 79. Brake housing; 80. Electromagnet; 81. Spring; 82. Armature; 83. Backing plate; 84. Connecting screw. Detailed Implementation

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details: like Figures 1-4 As shown, a transmission mechanism for a photoelectric turntable includes a reducer assembly 1, a motor assembly 2, and a brake assembly 3. The motor assembly 2 provides power, the reducer assembly 1 transmits power to the photoelectric turntable, and the brake assembly 3 applies braking. The motor assembly 2 includes a motor housing 36, a stator 37, and a rotor 38 housed within the motor housing 36. The reducer assembly 1 includes a hollow feedback shaft 6, an internal gear ring housing 10 with an internal gear ring on its inner wall, and three sets of planetary gears. The brake assembly 3 includes a brake housing 48 and a brake 50 housed within the brake housing 48. The motor housing 36, the internal gear ring housing 10, and the brake housing 48 are all cylindrical in shape, with openings at both ends. The motor housing 36 has a first annular flange and a second annular flange at each end, with the outer diameters of both being larger than the outer diameter of the motor housing 36 itself. The motor housing 36 is connected to the internal gear ring housing 10 via the first annular flange and multiple connecting bolts 4, and to the brake housing 48 via the second annular flange and multiple connecting bolts 5. This connection ensures that the motor housing 36 and the internal gear ring housing 10 are interconnected and communicate with each other, resulting in a more compact and integrated structure, a continuous transmission path, and precise installation and positioning. A sealing annular portion extending into the internal gear ring housing 10 is located at the end of the motor housing 36 with the first annular flange. A sealing ring is placed between the sealing annular portion and the inner wall of the internal gear ring housing 10, making the connection between the motor housing 36 and the internal gear ring housing 10 tighter and more secure, and providing excellent sealing performance.

[0024] like Figures 1-4 As shown, the three sets of planetary gear sets in the internal gear ring housing 10 are arranged sequentially along the axial direction of the feedback shaft 6. Each set of planetary gear sets includes a sun gear, planet gears, and a carrier. The planet gears of each set are meshed with the internal gear ring housing 10 and are respectively meshed with the sun gear in their respective sets. The feedback shaft 6 passes through each sun gear and carrier of each set of planetary gear sets.

[0025] like Figure 2 , Figure 3and Figure 7 As shown, the three planetary gear sets of the reducer assembly 1 are K1 planetary gear set 13, K2 planetary gear set 12, and K3 planetary gear set 11. The K1 sun gear 15 of the K1 planetary gear set 13 is connected to the rotor 38. The K2 sun gear 16 of the K2 planetary gear set 12 is connected to the K1 carrier 30 of the K1 planetary gear set 13 via a spline joint. The K3 sun gear 17 of the K3 planetary gear set 11 is connected to the K2 carrier 23 of the K2 planetary gear set 12 via a spline joint. A first connecting flange 26 is provided at the end of the K1 sun gear 15 connected to the rotor 38. The first connecting flange 26 extends into the motor housing 36 and is connected to the rotor 38 via a first bolt 44. An external gear ring structure 21 is provided at the end of the K1 sun gear 15 away from the rotor 38 for meshing with the planet gears 29 of the K1 planetary gear set.

[0026] like Figure 2 , Figure 5 and Figure 6 As shown, the K1 carrier 30 and K2 carrier 23 have the same structure, both including a frame with a central through hole for the feedback shaft 6 to pass through. An internal spline groove 25 is provided on one side of the frame. External spline structures 24, adapted to the internal spline groove 25, are correspondingly provided on one side of the K2 sun gear 16 and K3 sun gear 17. The external spline structure 24 of the K2 sun gear 16 meshes with the internal spline groove 25 of the K1 carrier 30, and the external spline structure 24 of the K3 sun gear 17 meshes with the internal spline groove 25 of the K2 carrier 23. Three planetary shafts 31 are evenly arranged along their circumference on the frame, each planetary shaft 31 mounting a planetary gear 29. The frame and the planetary gears 29 are connected by pins 28, and the planetary gears 29 are connected to the planetary shafts 31 by needle roller bearings 34. Oil passages 33 are provided on the planetary shafts 31 leading to the needle roller bearings 34, and oil nozzles 32 are provided in the oil passages 33. The grease nipple 32 can inject grease into the needle roller bearing 34 through the oil passage 33, ensuring that the rotational friction between the planetary gear 29 and the planetary shaft 31 always remains in a low-resistance state, thus extending the service life of the transmission components.

[0027] like Figure 2 , Figure 5 and Figure 7As shown, the K1 sun gear 15 is provided with a first bearing mounting part 76 and a second bearing mounting part 77. A first bearing 35 is mounted on the first bearing mounting part 76, and the K1 sun gear 15 is supported on the motor housing 36 through the first bearing 35. A second bearing is mounted on the second bearing mounting part 77, and the K1 sun gear 15 is connected to the K1 rotating frame 30 through the second bearing. The K2 sun gear 16 and K3 sun gear 17 are respectively provided with a third bearing mounting part and a fourth bearing mounting part. A third bearing 27 and a fourth bearing 20 are respectively mounted on the third bearing mounting part and the fourth bearing mounting part. The K2 sun gear 16 is connected to the K2 rotating frame 23 through the third bearing 27, and the K3 sun gear 17 is connected to the K3 rotating frame 7 through the fourth bearing 20.

[0028] like Figure 2 , Figure 4 and Figure 8 As shown, the K3 carrier 7 of the K3 planetary gear set 11 includes a frame for mounting the planetary gears 29 within the set. A support connection portion 62 is provided on the side of this frame away from the K2 carrier 23. The end of the support connection portion 62 has a connecting thread 66 for connecting to the photoelectric turntable. Multiple connecting thread holes 66 are evenly arranged along the circumferential direction of the end of the support connection portion 62. A first annular groove 64 is provided on the end of the support connection portion 62, inside each connecting thread hole 66. Multiple first mounting thread holes 65 are evenly arranged along the circumferential direction on the bottom wall of the first annular groove 64. A second connecting flange is provided at the end of the feedback shaft 6 connected to the K3 carrier 7. The second connecting flange is connected to the support connection portion 62 by a second bolt 18, and the threaded portion of the second bolt 18 is screwed into the first mounting thread hole 65, thus achieving synchronous rotational connection between the K3 carrier 7 and the feedback shaft 6. A first encoder 14 is mounted on the feedback shaft 6 by fastening screws 19, causing the first encoder 14 to rotate synchronously with the feedback shaft 6.

[0029] like Figure 2 , Figure 8 and Figure 9As shown, the end of the internal gear ring housing 10 away from the motor housing 36 has multiple threaded holes along its circumference for mounting the end cover 9. The end cover 9 is mounted on the end of the internal gear ring housing 10 by multiple third bolts 22. The end cover 9 is generally annular, and the support connection part 62 of the K3 frame 7 passes through the end cover 9. The end cover 9 has an inner extending annular part 67, the outer wall of which is in contact with the inner wall of the internal gear ring housing 10, and a sealing ring is provided between them to ensure the sealing between the end cover 9 and the internal gear ring housing 10. A fifth bearing mounting part 63 is provided on the support connection part 62, and a crossed roller bearing 8 is mounted on the fifth bearing mounting part 63. The inner ring and outer ring of the crossed roller bearing 8 are in contact with the inner walls of the fifth bearing mounting part 63 and the inner extending annular part 67, respectively. An oil seal mounting part 68 is provided on the support connection part 62. An oil seal is provided between the inner wall of the end cover 9 located on the outer side of the inner extended ring part 67 and the oil seal mounting part 68. The oil seal does not affect the rotation of the K3 swivel 7 and ensures sealing. A first snap ring groove 69 is provided between the oil seal mounting part 68 and the fifth bearing mounting part 63. A first snap ring for limiting the inner ring of the crossed roller bearing 8 is provided in the first snap ring groove 69. A plurality of second mounting threaded holes 70 are evenly provided along the circumference on the inner end face of the inner extended ring part 67. A ring retainer is installed in the second mounting threaded holes 70 by a fourth bolt. The ring retainer is used to limit the outer ring of the crossed roller bearing 8. In this way, the crossed roller bearing 8 is limited in both directions in the axial direction, avoiding its movement due to axial force during the rotation of the K3 swivel 7, and ensuring support accuracy and transmission stability.

[0030] like Figure 3 and Figure 11 As shown, the inner wall of the brake housing 48 is provided with a first annular connecting part and a second annular connecting part. The brake housing 78 of the brake 50 is connected to the first annular connecting part by multiple eighth bolts 49. A partition 51 is installed on the second annular connecting part by multiple ninth bolts 57. The end of the brake housing 48 away from the motor housing 36 is connected to a rear cover 52 by a fifth bolt 58. The rear cover 52 is provided with a through hole for the feedback shaft 6 to pass through. The partition 51 is located between the brake 50 and the rear cover 52.

[0031] like Figure 3 , Figure 10 , Figure 11As shown, the brake 50 has a friction disc 45, which is connected to a synchronously rotating brake sleeve 42. The brake sleeve 42 is connected to the rotor 38. A third connecting flange is provided at the end of the brake sleeve 42 connected to the rotor 38. The third connecting flange extends into the motor housing 36 and is connected to the rotor 38 by a sixth bolt 43. A sixth bearing mounting part is provided on the outer ring wall of the brake sleeve 42, and a sixth bearing 41 is mounted on the sixth bearing mounting part. The brake sleeve 42 is connected to the inner ring wall of the brake 50 through the sixth bearing 41. The feedback shaft 6 passes through the brake sleeve 42 and the friction disc 45. An external brake spline 47 is provided at the end of the brake sleeve 42 away from the rotor 38. An internal brake spline 46, which is adapted to the external brake spline 47, is provided on the inner wall of the friction disc 45. The external brake spline 47 is inserted into the internal brake spline 46, realizing the synchronous rotation of the brake sleeve 42 and the friction disc 45.

[0032] In this embodiment, the brake 50 uses an electromagnetic de-energizing brake, such as... Figure 14 As shown, the brake 50 includes a brake housing 78, a friction disc 45, an electromagnet 79, a spring 80, an armature 81, and a back plate 82. The brake housing 78 contains an annular electromagnet 79 and multiple circumferentially distributed springs 80. The back plate 82 is fixed to the brake housing 78 by a number of circumferentially distributed connecting screws 83 and a guide sleeve. The armature 81 passes through the guide sleeve and can slide along the axial direction of the guide sleeve. An axial gap is provided between the armature 81 and the friction disc 45. The brake inner spline 46 in the middle of the friction disc 45 is connected to the brake outer spline 47 of the brake sleeve 42. When the brake 50 is not energized, the annular electromagnet 79 has no magnetic force, and the spring force of the springs 80 is released, pressing the armature 81 and the friction disc 45 tightly against the back plate 82, limiting rotation through friction. When the brake 50 is energized, the annular electromagnet 79 generates magnetic force, which overcomes the elastic force of the spring 80 and attracts the armature 81. An axial gap is generated between the armature 81 and the friction disc 45, so that the friction disc 45 and the brake sleeve 42 can rotate synchronously.

[0033] like Figure 3 , Figure 12 and Figure 13 As shown, a bushing 40 is provided on the inner wall of the brake sleeve 42. The feedback shaft 6 passes through the bushing 40. The bushing 40 is interference-fitted with the inner wall of the brake sleeve 42 and clearance-fitted with the outer wall of the feedback shaft 6. The interference fit allows the bushing 40 to rotate synchronously with the brake sleeve 42, while the clearance fit allows the bushing 40 to support the feedback shaft 6 without hindering its rotation. Multiple grease grooves 75 are evenly arranged along the circumference of the inner wall of the bushing 40. These grooves store grease and provide lubrication when the feedback shaft 6 and the bushing 40 rotate slightly relative to each other, effectively reducing frictional loss between them.

[0034] like Figure 3 , Figure 12 and Figure 13 As shown, the brake sleeve 42 has a second annular groove at one end connected to the rotor 38. Multiple third mounting threaded holes for installing the limiting sleeve 71 are provided along the circumferential direction on the bottom wall of the second annular groove. A fourth connecting flange 73 is provided at the end of the limiting sleeve 71 connected to the brake sleeve 42. The fourth connecting flange 73 is connected to the second annular groove by a seventh bolt 74, and the threaded portion of the seventh bolt 74 is screwed into the third mounting threaded hole. The feedback shaft 6 passes through the limiting sleeve 71, and there is a certain gap between the feedback shaft 6 and the inner wall of the limiting sleeve 71. A limiting step 72 is provided on the inner wall of the brake sleeve 42 on the side of the bushing 40 away from the limiting sleeve 71. The limiting sleeve 71 connects with the bushing 40, pressing the bushing 40 tightly onto the limiting step 72. This axial clamping structure, through the limiting sleeve 71 and the limiting step 72, ensures that the bushing 40 is fixed in position within the brake sleeve 42, preventing displacement and thus maintaining the stability of the feedback shaft 6 support and the accuracy of the clearance fit.

[0035] like Figure 3 and Figure 11 As shown, a second encoder 39 is also mounted on the brake sleeve 42 by screws. The first encoder 14 has a first reading head 54, and the second encoder 39 has a second reading head 55. The first reading head 54 and the second reading head 55 are respectively mounted on the partition plate 51 by a number of ninth bolts 53 and a number of tenth bolts 56. A motor brake socket 59 and an encoder socket 61 are mounted on the rear cover 52. The motor brake socket 59 and the encoder socket 61 are respectively connected to the rear cover 52 by a number of eleventh bolts 60. The motor brake socket 59 is electrically connected to the motor assembly 2 and the brake 50, and the encoder socket 61 is electrically connected to the first encoder 14 and the second encoder 39.

[0036] Working principle of the invention: I. Power Output and Reduction Transmission like Figure 15As shown, when the motor assembly 2 is energized, the stator 37 generates an alternating magnetic field, driving the rotor 38 to rotate at high speed. The power of the rotor 38 is transmitted to the reducer assembly 1 and the brake assembly 3 through the connection structures at both ends, respectively. The power transmission path related to the reducer assembly 1 is as follows: the left end of the rotor 38 is rigidly connected to the first connecting flange 26 of the K1 sun gear 15 through the first bolt 44, driving the K1 sun gear 15 to rotate synchronously. The K1 sun gear 15 meshes with the planet gears 29 of the K1 planetary gear set 13 through the external gear ring structure 21. Under the constraint of the fixed internal gear ring housing 10, the planet gears 29 rotate around their own planetary shafts 31 while driving the K1 carrier 30 to rotate. Because the inner spline groove 25 of the K1 carrier 30 meshes with the outer spline structure 24 of the K2 sun gear 16, the revolution power of the K1 carrier 30 is transmitted to the K2 sun gear 16, driving the K2 planetary gear set 12 to repeat the motion of "sun gear driving planetary gears, planetary gears driving carrier". Similarly, the K2 carrier 23 drives the K3 sun gear 17 to rotate through the spline pair, and finally the power is output by the K3 carrier 7 of the K3 planetary gear set 11. Through the sequential meshing transmission of the three sets of planetary gear sets, a three-stage reduction structure is formed, which converts the high-speed, low-torque input of the rotor 38 into the low-speed, high-torque output of the K3 carrier 7, meeting the "reduction and torque increase" requirements of the photoelectric turntable. Finally, the power is connected to the photoelectric turntable through the support connection part 62 of the K3 carrier 7, realizing the final transmission of power.

[0037] During this process, the K1 sun gear 15 is supported on the motor housing 36 by the first bearing 35 and connected to the K1 rotating frame 30 by the second bearing; the K2 sun gear 16 is connected to the K2 rotating frame 23 by the third bearing 27, and the K3 sun gear 17 is connected to the K3 rotating frame 7 by the fourth bearing 20. The support of multiple sets of bearings ensures the coaxiality and stability during gear meshing.

[0038] II. Braking Control and Power Lock The right end of rotor 38 is connected to the third connecting flange of brake sleeve 42 via the sixth bolt 43, causing brake sleeve 42 to rotate synchronously. Brake sleeve 42 engages with brake internal spline 46 of friction disc 45 via brake external spline 47, causing friction disc 45 to rotate synchronously with rotor 38. Brake 50 uses electromagnetic braking principle to control the start and stop of rotor 38: when brake 50 is not energized, annular electromagnet 79 has no magnetic force, and the spring force of spring 80 releases, pressing armature 81 and friction disc 45 against back plate 82, limiting rotation through friction. When brake 50 is energized, annular electromagnet 79 generates magnetic force, which overcomes the spring force of spring 80 and attracts armature 81, creating an axial gap between armature 81 and friction disc 45, allowing friction disc 45 and brake sleeve 42 to rotate synchronously. The sixth bearing 41 provides stable support for the rotation of brake sleeve 42.

[0039] III. Closed-loop control of position and velocity To achieve high-precision positioning of the photoelectric turntable, the system constructs a closed-loop feedback mechanism using dual encoders: the second encoder 39 is mounted on the brake sleeve 42 with screws, rotating synchronously with the brake sleeve 42 and the rotor 38. Its second reading head 55 is fixed on the partition plate 51, detecting the original motion parameters of the rotor 38 in real time, such as its rotational speed and angle. The first encoder 14 is mounted on the feedback shaft 6 with fastening screws 19, and the feedback shaft 6 is rigidly connected to the K3 turntable 7 with the second bolt 18, rotating synchronously with the K3 turntable 7. Its first reading head 54 is also fixed on the partition plate 51, used to detect the terminal output motion parameters after three-stage deceleration. The detection signals from the two encoders are transmitted to the control system via encoder socket 61. The control system compares the terminal output parameters (signal from the first encoder 14) with the original input parameters (signal from the second encoder 39), calculates the deviation, and adjusts the power supply frequency or current of the motor assembly 2. Simultaneously, in conjunction with the braking action of the brake 50, the rotational state of the rotor 38 is corrected in real time to ensure the positional accuracy (positioning error ≤ 0.01°) and speed stability (speed fluctuation ≤ ±0.5%) of the photoelectric turntable. The motor brake socket 59 provides an interface for the power supply and signal control of the motor and brake, realizing integrated management of the electrical system.

[0040] Through the synergistic effect of power transmission, braking control and closed-loop feedback, the entire transmission mechanism realizes a complete working cycle of "power output - deceleration and torque increase - precise braking - real-time control", meeting the dual requirements of photoelectric turntable for power performance and control precision.

[0041] In summary, this invention significantly improves transmission accuracy and efficiency by integrating the motor assembly 2, reducer assembly 1, and brake assembly 3 into a single, interconnected structure, combined with the spline transmission of a multi-stage planetary gear set. Specifically, the internal gear ring housing 10 is connected and communicates with the motor housing 36, and the brake housing 48 is also connected and communicates with the motor housing 36, forming a compact power transmission channel. In the reducer assembly 1, the K1 sun gear 15 of the first-stage K1 planetary gear set 13 is connected to the rotor 38. The first set of carriers meshes with the external spline structure 24 of the second set of sun gears through the internal spline groove 25. This rigid spline engagement reduces the accumulated tooth backlash of traditional discrete gears. Simultaneously, the meshing transmission efficiency of the planetary gear set is far higher than that of worm gear transmission, overcoming the shortcoming of traditional transmission efficiency below 70%, making it more suitable for energy-constrained scenarios.

[0042] This invention optimizes spatial layout and reduces the impact of vibration coupling through an integrated housing design and hollow feedback shaft structure. The interconnected assembly of the motor housing 36, internal gear ring housing 10, and brake housing 48 reduces redundant connecting parts in a split structure, thus reducing the overall volume. The hollow feedback shaft 6 runs through each sun gear and the rotating frame, meeting the requirements for central wiring and optical path integration of the photoelectric turntable, breaking through the limitation of traditional mechanisms with a hollow aperture of less than 50mm, reaching 80mm. In addition, the integrated structure shortens the vibration transmission path, and the stable support of the needle roller bearing 34 between the planetary gears 29 and the planetary shaft 31 reduces the interference of high-frequency motor vibration on optical imaging equipment, avoiding imaging blurring problems during high-magnification observation.

[0043] This invention improves control accuracy and reduces dynamic response lag through a dual-encoder feedback and braking linkage design. The first encoder 14 on the feedback shaft 6 monitors the actual output position of the final stage K3 rotor 7, while the second encoder 39 on the brake sleeve 42 monitors the input motion state of the rotor 38. The dual encoder signals are transmitted to the control system via the encoder socket 61, achieving a closed-loop "input-output" comparison. This solves the problem that traditional single encoders cannot reflect the true position of the load end, keeping control lag error within a lower range. Simultaneously, the friction disc 45 of the brake 50 is linked to the brake external spline 47 of the brake sleeve 42 via the brake internal spline 46, enabling rapid response to braking demands and preventing target misses during rapid tracking.

[0044] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A transmission mechanism for an optoelectronic turntable, characterized in that, include: The motor assembly includes a motor housing, a stator, and a rotor disposed within the motor housing; The reducer assembly includes a hollow feedback shaft and an internal gear ring housing with an internal gear ring on its inner wall. The internal gear ring housing is connected to and communicates with a motor housing. Multiple sets of planetary gears are arranged sequentially along the axial direction of the feedback shaft within the internal gear ring housing. Each planetary gear set includes a sun gear, planet gears, and a carrier. The planet gears of each planetary gear set are meshed with the internal gear ring housing. The sun gear of the first-stage planetary gear set is connected to the rotor. The carrier of the preceding planetary gear set is connected to the sun gear of the following planetary gear set via a spline pair. The carrier of the last-stage planetary gear set is connected to the feedback shaft, and each sun gear is sleeved on the outside of the feedback shaft. A first encoder is mounted on the feedback shaft. A brake assembly includes a brake housing connected to and communicating with a motor housing; a brake with a friction disc is disposed in the brake housing, the friction disc is connected to a synchronously rotating brake sleeve, the brake sleeve is connected to a rotor, and a second encoder is mounted on the brake sleeve.

2. The transmission mechanism for a photoelectric turntable according to claim 1, characterized in that, The motor housing has a first annular flange and a second annular flange at both ends. The outer diameter of the first annular flange and the second annular flange is larger than the outer diameter of the motor housing body. The motor housing is connected to the internal gear ring housing through the first annular flange and to the brake housing through the second annular flange.

3. The transmission mechanism for an optoelectronic turntable according to claim 1, characterized in that, The reducer assembly includes three planetary gear sets: K1 planetary gear set, K2 planetary gear set, and K3 planetary gear set. The K1 sun gear of the K1 planetary gear set is connected to the rotor. The K2 sun gear of the K2 planetary gear set is connected to the K1 carrier of the K1 planetary gear set via a spline joint. The K3 sun gear of the K3 planetary gear set is connected to the K2 carrier of the K2 planetary gear set via a spline joint.

4. The transmission mechanism for a photoelectric turntable according to claim 3, characterized in that, The K1 and K2 rotating frames have the same structure, both including a frame. The frame has a central through hole for the feedback shaft to pass through. An internal spline groove is provided on one side of the frame. The K2 and K3 sun gears have corresponding external spline structures on one side that are adapted to the internal spline groove. The external spline structure of the K2 sun gear meshes with the internal spline groove of the K1 rotating frame, and the external spline structure of the K3 sun gear meshes with the internal spline groove of the K2 rotating frame. At least three planetary shafts are evenly arranged on the frame along its circumferential direction. Each planetary shaft is equipped with a planetary gear. The frame and the planetary gears are connected by pins. The planetary gears are connected to the planetary shafts by needle roller bearings. The planetary shafts are provided with oil passages leading to the needle roller bearings. Oil nozzles are provided in the oil passages.

5. A transmission mechanism for an optoelectronic turntable according to claim 4, characterized in that, The K3 carrier of the K3 planetary gear set includes a frame for mounting the planetary gears within the set. A support connection portion is provided on the side of the frame away from the K2 carrier. The end of the support connection portion is provided with a connecting thread for connecting to the photoelectric turntable. Multiple connecting thread holes are evenly arranged along the circumferential direction of the end of the support connection portion. A first annular groove is provided on the end of the support connection portion inside each connecting thread hole. Multiple first mounting thread holes are evenly arranged along the circumferential direction on the bottom wall of the first annular groove. A second connecting flange is provided at the end of the feedback shaft connected to the K3 carrier. The second connecting flange is connected to the support connection portion by a second bolt, and the threaded part of the second bolt is screwed into the first mounting thread hole.

6. A transmission mechanism for an optoelectronic turntable according to claim 5, characterized in that, An end cap is connected to the end of the internal gear ring housing away from the motor housing by a third bolt. The end cap is generally annular, and the support connection of the K3 frame passes through the end cap. The end cap has an inner extending annular portion, the outer wall of which is in contact with the inner wall of the internal gear ring housing, and a sealing ring is provided between them. A fifth bearing mounting portion is provided on the support connection portion, and a crossed roller bearing is mounted on the fifth bearing mounting portion. The inner ring and outer ring of the crossed roller bearing are in contact with the inner walls of the fifth bearing mounting portion and the inner extending annular portion, respectively.

7. A transmission mechanism for a photoelectric turntable according to claim 1, characterized in that, The feedback shaft passes through the brake sleeve and the friction disc. The brake sleeve has an external brake spline at the end away from the rotor. The friction disc has an internal brake spline that matches the external brake spline on its inner wall. The external brake spline is inserted into the internal brake spline to achieve synchronous rotation of the brake sleeve and the friction disc.

8. A transmission mechanism for a photoelectric turntable according to claim 7, characterized in that, A bushing is provided on the inner wall of the brake sleeve, and the feedback shaft passes through the bushing. The bushing is interference-fitted with the inner wall of the brake sleeve and clearance-fitted with the outer wall of the feedback shaft. A limiting sleeve is detachably installed at the end of the brake sleeve connected to the rotor, and the feedback shaft passes through the limiting sleeve. There is a certain gap between the feedback shaft and the inner wall of the limiting sleeve. A limiting step is provided on the inner wall of the brake sleeve on the side of the bushing away from the limiting sleeve. The limiting sleeve is connected to the bushing and presses the bushing tightly onto the limiting step. Multiple grease grooves are evenly provided on the inner wall of the bushing along its circumference.

9. A transmission mechanism for a photoelectric turntable according to claim 1, characterized in that, The brake housing is detachably connected to a rear cover at one end away from the motor housing, and the rear cover is provided with a through hole for the feedback shaft to pass through; the inner wall of the brake housing is provided with a first circular ring connecting part and a second circular ring connecting part, the brake is connected to the first circular ring connecting part, and a partition is installed on the second circular ring connecting part; the first encoder has a first reading head, the second encoder has a second reading head, and both the first reading head and the second reading head are installed on the partition.

10. A transmission mechanism for a photoelectric turntable according to claim 9, characterized in that, The rear cover is equipped with a motor brake socket and an encoder socket. The motor brake socket is electrically connected to the motor assembly and the brake, and the encoder socket is electrically connected to the first encoder and the second encoder.

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