Light and small frame type two-axis servo mechanism

Abstract

The invention discloses a light and small frame type two-axis servo mechanism which comprises a base, a frame and a load frame and further comprises an inner ring motor, an outer ring motor, an angular displacement sensor, a sensor demodulation module and the like. Under the limited conditions that the given mass of the two-axis servo mechanism is relatively small and a large search angle range is achieved in a relatively small enveloping space, the rotation axis of the inner ring assembly containing the load passes through the mass center of the inner ring assembly, the size of the enveloping space is fully utilized, the inner ring driving motor, the outer ring driving motor, the rotary transformer and the like are arranged and installed on the frame, and therefore the large search angle range is achieved. The rotating axis of the outer ring assembly containing the load is reasonably configured, the inner ring driving motor, the outer ring driving motor, the angular displacement sensor and the like are used as counterweights to balance the load mass, and it is guaranteed that the load does not exceed the enveloping space during rotating motion, so that additional balancing weights or few balancing weights do not need to be added; the mass center of the outer ring assembly containing the load can be configured on the rotation axis, the servo structure is compact, and the mass of the servo mechanism is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of stable platform servo mechanism technology, and in particular to a lightweight frame-type two-axis servo mechanism. Background Technology

[0002] A stabilizing platform servo mechanism is an electromechanical integrated device that achieves carrier attitude stabilization and precise target tracking through a servo control system. It is widely used in aerospace, aviation, marine and industrial fields, such as optoelectronic pods and robots.

[0003] Currently, in detection and tracking systems, the use of a stable platform servo mechanism can effectively eliminate and isolate the coupling effects of complex external motions on the detection and tracking system. However, the size of the stable platform servo mechanism needs to be designed according to the size of the equipment. Typically, the envelope space of the stable platform servo mechanism is relatively small, and the designed search angle range is relatively large. In addition, the size and mass of the load (detection and tracking system) are relatively large, which makes the remaining space at the end of the rotary shaft within the envelope space of the stable platform servo mechanism very small, making it difficult to install the motor and angle sensor at the end of the rotary shaft.

[0004] Meanwhile, within a limited envelope space, when using mechanical transmission, the configurable range of the rotation axes of the inner and outer ring components (taking a two-axis servo mechanism as an example) is narrow. In order to ensure that the rotational motion does not exceed the envelope space and to ensure that the center of mass of the inner and outer ring components is located on the rotation axis, it is often necessary to add counterweights to configure the center of mass on the rotation axis, resulting in the entire system being overweight. Summary of the Invention

[0005] To address the aforementioned problems, this invention aims to provide a lightweight, compact frame-type two-axis servo mechanism that fully utilizes the envelope space of the servo structure, rationally configures the rotation axis of the outer ring component containing the load, and balances the load mass. This eliminates the need for additional counterweights or requires very few counterweights, and positions the center of mass of the outer ring component containing the load on the rotation axis, effectively reducing the mass of the servo mechanism.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a lightweight frame-type two-axis servo mechanism, including a base, a frame and a load frame. The base is a U-shaped structure, consisting of a bottom plate and support plates vertically connected to both ends of the bottom plate. The bottom plate has mounting holes evenly spaced along its edge. A bearing is symmetrically embedded in the top of the support plate. A rotating shaft passes through the bearing. An arc-shaped internal tooth block is provided on the inner side of the support plate on the right side. The frame is a rectangular frame structure, including front, back, left and right frame plates. The left and right frame plates are fitted onto the first rotating shaft. The front and back frame plates are symmetrically embedded with the second bearings, and the second rotating shaft passes through the second bearings. A square frame is connected below the main frame. An inner ring angular displacement sensor is installed on the outer wall of the front frame plate of the square frame, and an inner ring motor is installed on the outer wall of the rear frame plate. A gear is installed on the motor shaft of the inner ring motor. The inner ring angular displacement sensor is coaxially connected to the inner ring motor through a connecting rod passing through the square frame. A sensor demodulation module is installed on the outer wall of the left frame plate of the square frame. An outer ring angular displacement sensor and an outer ring motor are coaxially connected and installed sequentially on the inner and outer walls of the right frame plate. A gear is installed on the motor shaft of the outer ring motor, and the gear meshes with the arc-shaped inner gear block. Both the inner ring angular displacement sensor and the outer ring angular displacement sensor are electrically connected to the sensor demodulation module. The inner ring angular displacement sensor, along with the inner ring motor and gear one, are used to set up counterweights on the front and rear sides of the square frame. The sensor demodulation module, along with the outer ring angular displacement sensor, the outer ring motor, and gear two, are used to set up counterweights on the left and right sides of the square frame. The load frame has a U-shaped structure, consisting of a load plate and connecting plates vertically connected to both ends of the load plate. The load plate has load connection holes evenly spaced, and the connecting plates are fitted onto the rotating shaft. An arc-shaped external tooth block is vertically arranged on the rear side below the load plate, and the arc-shaped external tooth block meshes with the gear. A vibration damper is arranged on the front side below the load plate, and a dual-axis gyroscope is arranged below the vibration damper. The overall mass of the square frame, inner ring angular displacement sensor, inner ring motor, gear one, connecting rod, sensor demodulation module, outer ring angular displacement sensor, outer ring motor, gear two, and arc-shaped inner tooth block is nearly balanced with the mass of the load device mounted above the load plate, thereby bringing the center of mass of the two-axis servo mechanism close to the axis of rotation.

[0007] Preferably, the inner wall of the support plate is provided with limit stops at a front-to-back distance below the left and right frame plates, and the limit stops are symmetrically arranged on both sides of the rotating shaft. A buffer sleeve is fitted on the limit stops to limit the front-to-back rotation angle of the frame.

[0008] Preferably, the inner walls of the front and rear frame plates of the frame are provided with limit stops at left and right intervals below the load plate, and the limit stops are symmetrically arranged on both sides of the rotating shaft. The limit stops are fitted with buffer sleeves to limit the left and right rotation angle of the load frame.

[0009] Preferably, horizontal connecting plates extend inward from the lower direction of the left and right side frame plates of the frame, the square frame is connected to the horizontal connecting plates, and weight reduction holes are provided on the horizontal connecting plates.

[0010] Preferably, the square frame and the horizontal connecting plate are connected by bolts.

[0011] Preferably, the square frame and the horizontal connecting plate are an integral structure.

[0012] Preferably, the front and rear frame plates of the frame are connected to the left and right frame plates by transition inclined plates, and weight reduction holes are provided on the transition inclined plates.

[0013] Preferably, the load plate has a weight reduction hole in the middle.

[0014] Preferably, a rectangular through hole is provided in the center of the base plate. After the size of the inner ring motor, the outer ring motor and the square frame are increased, the lower edge of the inner ring motor, the outer ring motor and the square frame can be embedded in the rectangular through hole and rotate back and forth.

[0015] The beneficial effects of this invention are as follows: within the relatively small envelope space of the two-axis servo mechanism, and under the constraints of achieving a large search angle range, a large load (detection and tracking system) size, a large overall mass, and the inability to use a direct-drive motor, this application, through reasonable configuration of the rotation axis, utilizes inner and outer ring motors and angular displacement sensors as counterweights to balance the load mass. It can effectively reduce the mass of the two-axis servo mechanism without the need for additional counterweights or with only a few additional counterweights, and has the characteristics of compact structure and light weight. Attached Figure Description

[0016] Figure 1 This is a structural diagram of the base of the present invention.

[0017] Figure 2 This is a structural diagram of the present invention.

[0018] Figure 3 This is a structural diagram of the load frame of the present invention.

[0019] Figure 4 This is an overall structural diagram of the two-axis servo mechanism of the present invention.

[0020] Figure 5 For the present invention Figure 4 Remove the base from the rear view.

[0021] Figure 6 This is a layout view of the two-axis servo mechanism transmission scheme of the present invention.

[0022] In the diagram: 2-Bearing cap; 31-Arc-shaped inner tooth block; 32-Arc-shaped outer tooth block; 41-Frame plate; 42-Horizontal connecting plate; 43-Transition inclined plate; 44-Square frame; 51-Inner ring angular displacement sensor; 52-Outer ring angular displacement sensor; 53-Sensor demodulation module; 61-Inner ring motor; 62-Outer ring motor; 71-Gear 1; 72-Gear 2; 8-Connecting rod; 91-Load plate; 91a-Load connection hole; 92-Connecting plate; 10-Vibration damper; 11-Base plate; 11a-Assembly hole; 11b-Rectangular through hole; 12-Support plate; 13-Dual-axis gyroscope; 14-Limit stop pin; a-Weight reduction hole. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0024] See attached document Figures 1-6 The illustrated lightweight frame-type two-axis servo mechanism includes a base, a frame, and a load cell. The base has a U-shaped structure, consisting of a base plate 11 and support plates 12 vertically connected to both ends of the base plate 11. The support plates 12 can be integrally manufactured with the base plate 11 or manufactured separately and then bolted together. Figure 1 As shown, the support plate 12 can preferably be configured as a stepped plate structure. While ensuring that the lateral width of the base plate 11 remains unchanged, the top spacing of the support plate 12 is increased, thereby increasing the envelope space within the servo mechanism. This facilitates the assembly of internal structural components such as motors and reduces the problem of limited envelope space.

[0025] like Figure 1 As shown, the base plate 11 has mounting holes 11a evenly spaced along its edge. The mounting holes 11a are used to install the base and all structural components (such as the frame, motor, load frame, and load) that constitute the servo mechanism on the equipment using the mounting bolts.

[0026] For the assembly of other structural components on the base, such as Figure 1 , 4 As shown, a bearing (not shown in the figure) is symmetrically embedded in the top of the support plate 12. A suitable adjusting washer is added at one point of the bearing to control the bearing clearance. A bearing cap 2 is provided on the outer wall of the support plate 12 to fix the bearing. A rotating shaft is inserted inside the bearing for the frame to rotate back and forth after assembly. An arc-shaped internal tooth block 31 is provided on the inner side of the support plate 12 on the right side, which cooperates with the gear 72 on the frame to drive the frame to rotate back and forth.

[0027] like Figure 2 , 4As shown, the frame is a rectangular frame structure, consisting of front, back, left and right frame plates 41. The left and right frame plates 41 are fitted onto the first rotating shaft. The front and back frame plates 41 are symmetrically embedded with bearings 2, and bearing caps 2 are provided on the outer walls of the front and back frame plates 41. The second rotating shaft 2 passes through the bearings 2. The left and right frame plates 41 are fitted onto the rotating shaft of the support plate 12 to realize the front and back rotation assembly of the frame on the base.

[0028] like Figure 2 , 4 As shown, a square frame 44 is connected below the frame. An inner ring angular displacement sensor 51 is installed on the outer wall of the front frame plate of the square frame 44, and an inner ring motor 61 is installed on the outer wall of the rear frame plate. A gear 71 is installed on the motor shaft of the inner ring motor 61. The inner ring angular displacement sensor 51 is coaxially connected to the inner ring motor 61 through a connecting rod 8 passing through the square frame 44, forming an inner ring drive mechanism. A sensor demodulation module 53 is installed on the outer wall of the left frame plate of the square frame. An outer ring angular displacement sensor 52 and an outer ring motor 62 are coaxially connected on the inner and outer walls of the right frame plate. A gear 72 is installed on the motor shaft of the outer ring motor 62 (the tooth backlash can be eliminated by adding appropriate adjusting washers at the arc-shaped inner tooth block 31 and arc-shaped outer tooth block 32), forming an outer ring drive mechanism. The second gear 72 meshes with the arc-shaped inner tooth block 31, and is driven to rotate by the outer ring motor 62. The second gear 72 rotates along an arc on the arc-shaped inner tooth block 31, causing the frame to rotate back and forth on the bearing of the support plate 12. At the same time, the rotation angle is controlled by the outer ring angular displacement sensor 52. Both the inner ring angular displacement sensor 51 and the outer ring angular displacement sensor 52 are electrically connected to the sensor demodulation module 53 to control the rotation angle of the frame and load frame driven by the inner ring motor 61 and the outer ring motor 62.

[0029] This application aims to address the problem of excessive system weight caused by adding counterweights to realign the center of gravity onto the rotation axis when assembling structural components within the limited envelope space of a servo mechanism. Figure 5-6 As shown, the inner ring angular displacement sensor 51, the inner ring motor 61, and the first gear 71 are used to set up counterweights on the front and rear sides of the square frame 44. The sensor demodulation module 53, the outer ring angular displacement sensor 52, the outer ring motor 62, and the second gear 72 are used to set up counterweights on the left and right sides of the square frame 44. This allows the center of mass to be positioned closer to the axis of rotation, thereby effectively solving the problem of the current need for additional counterweights, which leads to the overweight of the entire system.

[0030] like Figure 3-4As shown, the load frame is a U-shaped integrated structure, including a load plate 91 and connecting plates 92 vertically connected to both ends of the load plate 91. The load plate 91 has evenly spaced load connection holes 91a for assembling loads (such as a detection and tracking system). The connecting plates 92 are mounted on the rotating shaft, allowing the load frame to rotate left and right, forming a two-axis servo mechanism with the frame's forward and backward rotation. An arc-shaped external toothed block 32 is vertically arranged on the rear side below the load plate 91. The arc-shaped external toothed block 32 meshes with the gear 71. Driven by the inner ring motor 61 and the gear 71, the load frame rotates left and right, and the rotation angle is controlled by the inner ring angular displacement sensor 51.

[0031] To detect the current attitude of the payload (detection and tracking system), such as Figure 3 As shown, a vibration damper 10 is provided on the front side below the load plate 91, and a dual-axis gyroscope 13 is provided below the vibration damper 10. The vibration damper 10 improves the mechanical environment adaptability of the dual-axis gyroscope 13. The dual-axis gyroscope 13 can detect the current attitude of the load and feed it back to the inner ring motor 61 and the outer ring motor 62, driving gear 1 71 and gear 2 72 to rotate. At the same time, after detection by the inner ring angular displacement sensor 51 and the outer ring angular displacement sensor 52, closed-loop control is achieved through the sensor demodulation module 53.

[0032] Based on the structural components assembled on the aforementioned square frame 44 achieving a center of mass close to the rotation axis of the square frame 44, to further bring the center of mass of the entire two-axis servo mechanism closer to the rotation axis, as follows: Figure 4-5 As shown, the square frame 44, inner ring angular displacement sensor 51, inner ring motor 61, gear 1 71, connecting rod 8, sensor demodulation module 53, outer ring angular displacement sensor 52, outer ring motor 62, gear 2 72, and arc-shaped inner tooth block 31 are all arranged below the base, while the load device mounted on the load plate 91 is arranged above the base, so that the mass of the upper and lower parts of the base is nearly balanced, thereby allowing the center of mass of the two-axis servo mechanism to be further close to the axis of rotation, solving the problem of the current need to add counterweights, which leads to the overweight of the whole system.

[0033] To limit the front and rear rotation angle of the frame, such as Figure 4 As shown, limit stops 14 are provided on the inner wall of the support plate 12 and below the left and right frame plates 41 at a front-to-back distance. The limit stops 14 are symmetrically arranged on both sides of the pivot, so that the frame 1 can contact the limit stops 14 when rotating back and forth by the same angle. A buffer sleeve (preferably made of aviation rubber) is fitted on the limit stops 14. The limit stops 14 can limit the front-to-back rotation angle of the frame, and the buffer sleeve can buffer the force when contacting, realizing soft limiting and preventing damage to the load, dual-axis gyroscope 13, etc. when the servo system loses control and overshoots.

[0034] Similarly, to limit the left and right rotation angle of the load frame, such as Figure 4 As shown, the inner walls of the front and rear frame plates 41 of the frame and the load plate 91 are provided with limit stops 14 at left and right intervals. The limit stops 14 are symmetrically arranged on both sides of the rotating shaft. The limit stops 14 are fitted with buffer sleeves. The left and right rotation angle of the load frame is limited by the limit stops 14, which can also prevent damage to the load, dual-axis gyroscope 13, etc. when the servo system goes out of control and overshoots.

[0035] like Figure 5 As shown, after assembling structural components such as the inner ring motor 61 and the outer ring motor 62 onto the square frame 44, to improve integration and reduce weight, the size of the square frame 44 after assembling the structural components is smaller than the frame size. Therefore, to facilitate the connection between the square frame 44 and the frame, as shown... Figure 2 , 4 As shown, horizontal connecting plates 42 extend inward from the lower direction of the frame plates 41 on the left and right sides of the frame, and the square frame 44 can be connected to the frame through the horizontal connecting plates 42. In order to reduce weight, weight reduction holes a are provided on the horizontal connecting plates 42.

[0036] Preferably, the square frame 44 can be manufactured separately and then assembled and connected to the frame with the horizontal connecting plate 42 by bolts.

[0037] In another preferred embodiment, the square frame 44 and the horizontal connecting plate 42 are integrally connected, that is, a frame is machined from a blank and integrally formed with the square frame 44, that is, the entire frame is an integral structure.

[0038] To further reduce the weight of the frame, such as Figure 2 , 4 As shown, the front and rear frame plates 41 and the left and right frame plates 41 of the frame are connected by a transition inclined plate 43. The transition inclined plate 43 can reduce the perimeter of the frame, and reduce the weight of the frame while ensuring the basic connection and assembly structure of the frame. At the same time, a weight reduction hole a is provided on the transition inclined plate 43 to further reduce the weight of the frame.

[0039] Similarly, to reduce the weight of the load plate 91, such as Figure 3 As shown, a weight-reduction hole a is provided in the middle of the load plate 91. Through the miniaturization and integration of the square frame 44, and the setting of multiple weight-reduction holes a and transition ramp 43, the overall weight of the two-axis servo mechanism is reduced.

[0040] like Figure 1 , 4As shown, a rectangular through hole 11b is provided in the base plate 11. After the size of the inner ring motor 61, the outer ring motor 62, and the square frame 44 increases, the lower edges of the inner ring motor 61, the outer ring motor 62, and the square frame 44 can be embedded in the rectangular through hole 11b and rotate back and forth. This not only enables the assembly of large-sized motors, but also balances the increased weight of the motors through the rectangular through hole 11b, while still ensuring the normal operation of the entire servo mechanism.

[0041] The working principle of the two-axis servo mechanism of this invention is as follows: The current attitude of the load (reflected on the load plate 91) is detected by a dual-axis gyroscope 13. This attitude is then fed back to the inner ring motor 61 or the outer ring motor 62 via the control system. The inner ring motor 61 drives gear 71, which in turn rotates the arc-shaped outer gear block 32 on the load frame, thereby adjusting the left and right deflection angle of the load. This angle adjustment is detected by the inner ring angular displacement sensor 51 and then controlled in a closed loop via the sensor demodulation module 53. Similarly, the outer ring motor 62 drives gear 72 to rotate on the arc-shaped inner gear block 31 on the base plate 11. This rotation is transmitted to the frame via the square frame 44. The frame rotates back and forth on the support plate 12 via a rotating shaft, thereby driving the load to rotate back and forth, thus realizing the action of the two-axis servo mechanism. The control system can connect the inner ring motor 61 and the outer ring motor 62 in series to achieve synchronous movement of the two axes.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by the present invention.

Claims

1. A lightweight, compact frame-type two-axis servo mechanism, characterized in that: It includes a base, a frame and a load frame. The base is a U-shaped structure, consisting of a bottom plate and support plates vertically connected to both ends of the bottom plate. The bottom plate has evenly spaced mounting holes along its edges. A bearing is symmetrically embedded in the top of the support plate. A rotating shaft passes through the bearing. An arc-shaped internal tooth block is provided on the inner side of the support plate on the right side. The frame is a rectangular frame structure, including front, back, left and right frame plates. The left and right frame plates are fitted onto the first rotating shaft. The front and back frame plates are symmetrically embedded with the second bearings, and the second rotating shaft passes through the second bearings. A square frame is connected below the main frame. An inner ring angular displacement sensor is installed on the outer wall of the front frame plate of the square frame, and an inner ring motor is installed on the outer wall of the rear frame plate. A gear is installed on the motor shaft of the inner ring motor. The inner ring angular displacement sensor is coaxially connected to the inner ring motor through a connecting rod passing through the square frame. A sensor demodulation module is installed on the outer wall of the left frame plate of the square frame. An outer ring angular displacement sensor and an outer ring motor are coaxially connected and installed sequentially on the inner and outer walls of the right frame plate. A gear is installed on the motor shaft of the outer ring motor, and the gear meshes with the arc-shaped inner gear block. Both the inner ring angular displacement sensor and the outer ring angular displacement sensor are electrically connected to the sensor demodulation module. The inner ring angular displacement sensor, along with the inner ring motor and gear one, are used to set up counterweights on the front and rear sides of the square frame. The sensor demodulation module, along with the outer ring angular displacement sensor, the outer ring motor, and gear two, are used to set up counterweights on the left and right sides of the square frame. The load frame has a U-shaped structure, consisting of a load plate and connecting plates vertically connected to both ends of the load plate. The load plate has load connection holes evenly spaced, and the connecting plates are fitted onto the rotating shaft. An arc-shaped external tooth block is vertically arranged on the rear side below the load plate, and the arc-shaped external tooth block meshes with the gear. A vibration damper is arranged on the front side below the load plate, and a dual-axis gyroscope is arranged below the vibration damper. The overall mass of the square frame, inner ring angular displacement sensor, inner ring motor, gear one, connecting rod, sensor demodulation module, outer ring angular displacement sensor, outer ring motor, gear two, and arc-shaped inner tooth block is nearly balanced with the mass of the load device mounted above the load plate, thereby bringing the center of mass of the two-axis servo mechanism close to the axis of rotation.

2. The two-axis servo mechanism according to claim 1, characterized in that: The inner wall of the support plate and below the left and right frame plates are provided with limit stops at a front-to-back distance. The limit stops are symmetrically arranged on both sides of the rotating shaft. A buffer sleeve is fitted on the limit stops to limit the front-to-back rotation angle of the frame.

3. The two-axis servo mechanism according to claim 1, characterized in that: Limiting pins are provided on the inner walls of the front and rear frame plates of the frame and at left and right intervals below the load plate. The limiting pins are symmetrically arranged on both sides of the second rotating shaft. A buffer sleeve is fitted on the limiting pin, thereby limiting the left and right rotation angle of the load frame.

4. The two-axis servo mechanism according to claim 1, characterized in that: The left and right side frame plates of the frame have horizontal connecting plates extending inward from the bottom. The square frame is connected to the horizontal connecting plates, and the horizontal connecting plates have weight-reducing holes.

5. The two-axis servo mechanism according to claim 4, characterized in that: The square frame and the horizontal connecting plate are assembled and connected by bolts.

6. The two-axis servo mechanism according to claim 4, characterized in that: The square frame and the horizontal connecting plate are an integral structure.

7. The two-axis servo mechanism according to claim 1, characterized in that: The front and rear frame plates of the frame are connected to the left and right frame plates by transition inclined plates, and weight reduction holes are provided on the transition inclined plates.

8. The two-axis servo mechanism according to claim 1, characterized in that: The load plate has a weight reduction hole in the middle.

9. The two-axis servo mechanism according to claim 1, characterized in that: A rectangular through hole is provided in the center of the base plate. After the size of the inner ring motor, the outer ring motor and the square frame are increased, the lower edge of the inner ring motor, the outer ring motor and the square frame can be embedded in the rectangular through hole and rotate back and forth.

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