Two-dimensional rotary table

Abstract

The utility model provides a two-dimensional rotary table. The two-dimensional rotary table comprises two gear and worm transmission pairs. The first set of gear worm transmission pair is mounted on the base, and a motor drives a worm to rotate to drive a gear to rotate; and the input of the second set of gear worm transmission pair drives the worm to rotate by the motor, and the gear shaft is used as the output and is used as a mounting load. The first set of gear and worm transmission pair is connected with the second set of gear and worm transmission pair through a connecting piece; according to the two-dimensional rotary table, due to the fact that a gear and worm transmission mechanism is adopted, linear contact meshing transmission is achieved, a transmission gap can be eliminated, and stable and accurate rotation and pitching two-degree-of-freedom movement of a load is achieved through a simple mechanical structure mode and low manufacturing cost.

Description

Technical Field

[0001] The present application relates to a turntable for loading a load, and in particular to a two-dimensional turntable. Background Art

[0002] Satellite antennas are essential components for the normal operation of satellites. Satellite antennas are mounted on a two-dimensional turntable to achieve rotation with two degrees of freedom. Traditionally, this type of two-dimensional turntable is constructed using an antenna motion mechanism with a harmonic reducer as the main reduction mechanism. Due to the structural complexity of the harmonic reducer itself, the cost is very high. With the almost geometric growth in the number of satellites, a two-dimensional turntable with a simple structure, low cost, reliability and durability has become an important issue that needs to be solved in the field of aerospace technology. In addition, the harmonic reducer cannot achieve a hollow structure, and the wire passing is more complicated. Utility Model Content

[0003] In view of the above problems, the present application aims to propose a two-dimensional turntable, which has a simple structure, low cost, reliability and durability; the present application also aims to propose a two-dimensional turntable, which is convenient for cables to pass through.

[0004] The two-dimensional turntable of the present application comprises: a base, a first gear worm transmission pair, and a second gear worm transmission pair;

[0005] A base; the base includes a mounting shaft;

[0006] The first gear worm transmission pair comprises: a first gear assembly, a first worm assembly; the first worm assembly comprises: a first worm, the first worm is a double-conical worm comprising a first conical worm and a second conical worm; both ends of the first worm are supported by a first worm bearing seat and a first bearing; a first drive motor is connected to the first worm for driving the first worm; the first conical worm of the first worm is used to form a line contact meshing with the first gear assembly on a first side, and the second conical worm of the first worm is used to form a line contact meshing with the first gear assembly on a second side;

[0007] The first gear worm transmission pair is installed on the mounting shaft of the base through the first gear assembly; the first gear assembly is driven by the first worm assembly to perform a rotary motion around the mounting shaft of the base;

[0008] The second gear-worm transmission pair includes a second gear assembly and a second worm assembly; the second worm assembly includes: a second worm, the second worm is a double-conical worm including a third conical worm and a fourth conical worm; both ends of the second worm are supported by a second worm bearing seat and a second bearing; a second drive motor is connected to the second worm for driving the second worm; the third conical worm of the second worm is used to form a line contact meshing with the second gear assembly on the first side, and the fourth conical worm of the second worm is used to form a line contact meshing with the second gear assembly on the second side;

[0009] The second gear-worm transmission pair is connected to the first gear-worm transmission pair through an adapter; the adapter is formed into an inverted T-shape including a horizontal plate and a vertical plate; the lower end of the horizontal plate is fixedly connected to the first gear assembly of the first gear-worm transmission pair, and the upper end of the horizontal plate is fixedly connected to the second worm bearing seat of the second gear-worm transmission pair; the vertical plate is used to install the output shaft bearing seat;

[0010] The second gear assembly of the second gear worm transmission pair is coaxially fixedly connected with the output shaft; the output shaft is used to install the load; the output shaft is installed in the output shaft bearing seat.

[0011] Preferably, the first gear assembly includes a first gear and a second gear; the first gear and the second gear are coaxially stacked and connected; the first gear and the second gear are offset in the circumferential direction; the first conical worm of the first worm forms a line contact meshing with the first gear on the first side, and the second conical worm of the first worm forms a line contact meshing with the second gear on the second side.

[0012] Preferably, the second gear assembly includes a third gear and a fourth gear; the third gear and the fourth gear are coaxially stacked and connected; the third gear and the fourth gear are offset in the circumferential direction; the third conical worm of the second worm forms a line contact meshing with the third gear on the first side, and the fourth conical worm of the second worm forms a line contact meshing with the fourth gear on the second side.

[0013] Preferably, at least one of the mounting shaft and the output shaft is a hollow shaft for passing a cable of a load.

[0014] Preferably, the first elastic block is inserted and installed in the first gear and the second gear of the stacked first gear assembly, so that appropriate relative rotation is allowed between the first gear and the second gear.

[0015] Preferably, the second elastic block is inserted into the third gear and the fourth gear of the stacked second gear assembly to allow appropriate relative rotation between the third gear and the fourth gear.

[0016] Preferably, the first worm is a split structure, and one of the first conical worm and the second conical worm can move along the axial direction of the first worm.

[0017] Preferably, the second worm is a split structure, and one of the third conical worm and the fourth conical worm can move along the axial direction of the first worm.

[0018] Preferably, the first worm or the second worm includes a disc spring component and a nut, the disc spring component is used to provide a clamping force to the movable first conical worm, the second conical worm, the third conical worm or the fourth conical worm; the nut is used to adjust the clamping force by adjusting its position on the corresponding first worm or second worm.

[0019] Preferably, the load is an antenna or a camera.

[0020] The two-dimensional turntable of the present application realizes the smooth and precise movement of the rotation and pitching of the load through two sets of gear worm pairs with a simple mechanical structure and low cost. The two-dimensional turntable of the present application is convenient for the load cable to pass through through the hollow shaft design of the mounting shaft or output shaft.

[0021] The two-dimensional turntable of this application also has the following advantages:

[0022] 1. Gears can be easily processed precisely, thus creating conditions for achieving precise transmission;

[0023] 2. The gear worm transmission pair has the basic advantages of large transmission ratio and stable transmission of worm transmission. At the same time, the worm here is a structure that realizes line contact transmission with the gear, which has a greater load-bearing capacity. The worm can also be easily precision-machined, creating conditions for achieving precision transmission;

[0024] 3. As a worm drive with a large transmission ratio, it can achieve self-locking motion;

[0025] 4. It is easier to achieve a hollow structure, which is convenient for wires to pass through;

[0026] 5. Simple structure, only two sets of special but easy-to-manufacture worm gears are needed;

[0027] 6. Low cost: Gears and worms are the two most important basic components, and both have mature and low-cost processing and manufacturing methods.

[0028] 7. Because of its simple structure, large transmission ratio and large load-bearing capacity, the size and mass of the object can be small.

[0029] 8. Eliminate the rotation error caused by gear gap when switching between forward and reverse directions (anti-backlash). The transmission form used can completely eliminate the transmission gap. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1a This is a schematic diagram of the main cross-sectional structure of the two-dimensional turntable of the present application;

[0031] Figure 1b It is a schematic diagram of the side cross-sectional structure of the two-dimensional turntable of the present application;

[0032] Figure 1c This is a schematic diagram of the top view of the two-dimensional turntable of the present application;

[0033] Figure 2 A schematic diagram of the gear worm transmission meshing and backlash elimination principle of an embodiment of the two-dimensional turntable of the present application;

[0034] Figure 3 A schematic structural diagram of another embodiment of the two-dimensional turntable for eliminating gaps of the present application;

[0035] Figure 4a , Figure 4b , Figure 4c This is another implementation of the two-dimensional turntable of the present application as a satellite antenna attitude adjustment mechanism. DETAILED DESCRIPTION

[0036] like Figure 1a , Figure 1b , Figure 1c As shown, the base 1 has a mounting shaft in the middle.

[0037] The gear worm transmission pair is composed of a gear assembly and a worm assembly. The gear assembly is composed of coaxially stacked and fixedly connected gears 21 and 22. The worm assembly is composed of a worm 23, a worm bearing seat and a bearing 24 and a drive motor 25. The worm assembly and the gear assembly are installed at 90° staggered, with a center distance A. The worm 23 is a part that is approximately "dumbbell-shaped", and the conical worms on both sides form a line contact meshing relationship with the gear 21 and the gear 22 respectively. By adjusting the relative circumferential positions of the gears 21 and 22, they are in close contact with the tooth surfaces of the meshing gears respectively, thereby eliminating the meshing clearance. The bearing seat 24 of the worm 23 is fixed on the base 1 to ensure the center distance A and the 90° staggered relationship.

[0038] The gear 21 is connected to the mounting shaft of the base 1 through the bearing 11. The gear assembly can rotate around the mounting shaft of the base under the drive of the worm. The worm is driven by the motors at both ends. The motors are installed at both ends to reduce the volume. The worm can also be driven by a motor installed at only one end.

[0039] The adapter 31 is used as a transitional connection member between the second set of gear worm transmission mechanism and the first set of gear worm mechanism. It has a shape similar to an inverted T. The lower end is fixedly connected to the gears 21 and 22, and the second set of worm bearing seats are fixed thereon. The vertical plate is used as the output shaft bearing seat.

[0040] The worm 32 is fixed to the adapter 31 through a bearing seat and a bearing 38. The worm is driven by a motor 39 installed at both ends to achieve rotational motion.

[0041] Gears 33 and 34 are coaxially stacked and fixedly installed. They can be incomplete gears. The gear and the output shaft 35 are coaxially fixedly installed through a expansion sleeve 36. The output shaft is connected to the output shaft bearing seat on the adapter through an angular contact ball bearing 37 and its gland. The gear can drive the output shaft to rotate. The axis of the output shaft is perpendicular to the axis of the gear of the first set of gear worm mechanism, and the axes intersect or stagger.

[0042] The transmission ratio of the gear worm transmission mechanism generally adopts a single-head worm, so the transmission ratio is the number of gear teeth.

[0043] The installation center distance between the gear and the worm is A1.

[0044] The load may be an antenna or other objects, such as a camera, and is fixed on the output shaft 35 in an appropriate manner.

[0045] The working process is as follows.

[0046] The first set of gear and worm transmission mechanism drives the gear and the second set of gear and worm mechanism on it and the load to make a rotational motion of not less than 360°; the second set of gear and worm transmission mechanism drives the load to make a pitch rotational motion of not less than ±90°. The two rotational motions can work simultaneously to achieve two-degree-of-freedom linkage motion. Due to the properties of worm transmission, the transmission mechanism can be self-locking even if the friction coefficient is very small. Due to the special line contact worm-gear transmission, it has greater load-bearing capacity and wear-resistant properties. Due to the basic properties of worm transmission, the transmission is smooth, without noise and vibration.

[0047] The coaxially stacked gears can be fixed mechanically (for example, by screw fastening) or by elastic elements, so that the two gears are always tightly meshed with the worm tooth surface to avoid clearance caused by wear.

[0048] The structure form to eliminate the gap is as follows Figure 2 The elastic block 42 is located between the two stacked gears 33 and 34. The pressure plate 41 is fastened to the gear 34 to ensure that the gear 33 does not move axially, but allows the gear 33 to rotate slightly in the circumferential direction relative to the gear 34. The torque is transmitted through the elastic block to compensate for the gap caused by wear. The structural form and working principle of the two sets of gear worm transmission mechanisms are similar.

[0049] The above about Figure 1a , 1b , 1c and Figure 2 In the introduction, the gears are offset and stacked to eliminate the backlash. For occasions with relatively low precision requirements, Figure 1a , 1b , 1c and Figure 2 The two stacked gears in the diagram are replaced by one gear.

[0050] Another structural form to eliminate the gap is to divide the worm into two parts. One of the worms 44 can move axially along the worm shaft, such as Figure 3 The position and the pressing force are adjusted by turning the nut through a set of disc spring components 43. Figure 3 The gear in is a gear, not a Figure 1a , 1b, 1c and Figure 2 The two stacked gears in the machine are designed to eliminate backlash through the two-body design of the worm.

[0051] There are many ways to combine the two sets of gear and worm mechanisms to form installation platforms for antenna loads with different requirements and different structural forms. Figure 4a , 4b As shown in FIG. 4c, the antenna structure can be installed on the left side of the second set of gear worm mechanisms, and can have a larger antenna size space, that is, a smaller driving mechanism can be used to drive the movement of an antenna of larger specifications.

[0052] The relative position relationship of the two sets of gear worm transmission mechanisms in this application can be adjusted as needed. The core rule is to adapt to the specific conditions such as the shape, size, range of motion, mass size, etc. of the load (antenna).

[0053] The gear and worm structure of the present application is disclosed in detail in CN 101334091 B. The present application only utilizes it to construct a two-dimensional rotating platform, and the present application does not involve improvements to the gear and worm pair.

[0054] Unless otherwise defined, all technical and / or scientific terms used in this application have the same meanings as those commonly understood by those skilled in the art to which the present invention relates. The materials, methods and embodiments mentioned in this application are illustrative only and not restrictive.

[0055] Although the present invention has been described in conjunction with specific implementation methods, those skilled in the art may make appropriate substitutions, modifications and changes within the scope of the invention of this application, and such substitutions, modifications and changes still fall within the scope of protection of this application.

Claims

1. A two-dimensional turntable, characterized in that include: A base, a first gear-worm transmission pair, and a second gear-worm transmission pair; Pedestal; The base includes a mounting shaft; The first gear-worm transmission pair comprises: a first gear assembly, a first worm assembly; the first worm assembly comprises a first worm; the first worm is a double-conical worm comprising a first conical worm and a second conical worm; both ends of the first worm are supported by a first worm bearing seat and a first bearing; a first drive motor is connected to the first worm for driving the first worm; the first conical worm of the first worm is used to form a line contact meshing with the first gear assembly on a first side, and the second conical worm of the first worm is used to form a line contact meshing with the first gear assembly on a second side; The first gear worm transmission pair is installed on the mounting shaft of the base through the first gear assembly; the first gear assembly is driven by the first worm assembly to perform a rotary motion around the mounting shaft of the base; The second gear-worm transmission pair includes a second gear assembly and a second worm assembly; the second worm assembly includes a second worm; the second worm is a double-conical worm including a third conical worm and a fourth conical worm; both ends of the second worm are supported by a second worm bearing seat and a second bearing; a second drive motor is connected to the second worm for driving the second worm; the third conical worm of the second worm is used to form a line contact meshing with the second gear assembly on the first side, and the fourth conical worm of the second worm is used to form a line contact meshing with the second gear assembly on the second side; The second gear-worm transmission pair is connected to the first gear-worm transmission pair through an adapter; the adapter is formed into an inverted T-shape including a horizontal plate and a vertical plate; the lower end of the horizontal plate is fixedly connected to the first gear assembly of the first gear-worm transmission pair, and the upper end of the horizontal plate is fixedly connected to the second worm bearing seat of the second gear-worm transmission pair; the vertical plate is used to install the output shaft bearing seat; The second gear assembly of the second gear worm transmission pair is coaxially fixedly connected with the output shaft; the output shaft is used to install the load; the output shaft is installed in the output shaft bearing seat.

2. The two-dimensional turntable according to claim 1, characterized in that: The first gear assembly includes a first gear and a second gear; the first gear and the second gear are coaxially stacked and connected; the first gear and the second gear are offset in the circumferential direction; the first conical worm of the first worm forms a line contact meshing with the first gear on the first side, and the second conical worm of the first worm forms a line contact meshing with the second gear on the second side.

3. The two-dimensional turntable according to claim 1, characterized in that: The second gear assembly includes a third gear and a fourth gear; the third gear and the fourth gear are coaxially stacked and connected; the third gear and the fourth gear are offset in the circumferential direction; the third conical worm of the second worm forms a line contact meshing with the third gear on the first side, and the fourth conical worm of the second worm forms a line contact meshing with the fourth gear on the second side.

4. The two-dimensional turntable according to claim 1, characterized in that: At least one of the installation shaft and the output shaft is a hollow shaft for passing a cable of a load.

5. The two-dimensional turntable according to claim 2, characterized in that: The first elastic block is inserted and installed in the first gear and the second gear of the stacked first gear assembly so that appropriate relative rotation is allowed between the first gear and the second gear.

6. The two-dimensional turntable according to claim 3, characterized in that: The second elastic block is inserted into the third gear and the fourth gear of the stacked second gear assembly so that appropriate relative rotation is allowed between the third gear and the fourth gear.

7. The two-dimensional turntable according to claim 1, characterized in that: The first worm is a split structure, and one of the first conical worm and the second conical worm can move along the axial direction of the first worm.

8. The two-dimensional turntable according to claim 1, characterized in that: The second worm is a split structure, and one of the third conical worm and the fourth conical worm can move along the axial direction of the first worm.

9. The two-dimensional turntable according to claim 7 or 8, characterized in that: The first worm or the second worm includes a disc spring component and a nut. The disc spring component is used to provide a clamping force to the movable first conical worm, the second conical worm, the third conical worm or the fourth conical worm; the nut is used to adjust the clamping force by adjusting its position on the corresponding first worm or the second worm.

10. The two-dimensional turntable according to claim 1, characterized in that: The load is an antenna or a camera.

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