Backlash-free rotary table rotating structure

Abstract

This application relates to the field of rotary structure technology, and more particularly to a backlash-free rotary table structure, comprising: a main shaft and a bushing, the bushing being sleeved on the main shaft and rotating relative to the main shaft; a rotating platform connected to the bushing; and a bracket disposed between the main shaft and the bushing, the bracket having a plurality of balls embedded therein, the balls abutting against at least one of the main shaft and the bushing. This application achieves an interference fit between the bushing and the ball bearing assembly to eliminate backlash, while also allowing the main shaft and the bushing to rotate relative to each other under the action of the ball bearing assembly. The bushing always rotates around the main shaft, and the ball bearing design results in low frictional damping, enhancing the rotary stability and wear resistance of the rotary table.

Description

Technical Field

[0001] This application relates to the field of rotating structure technology, and in particular to a backlash-free rotary table rotating structure. Background Technology

[0002] In the field of products such as laser levels, the initial approach was to keep the machine stationary and passively measure the target object to achieve the desired function. As the market developed, there was a need for laser levels to actively measure the target object to achieve the desired function. This technology, as a device that works with laser levels, can enable the laser level and other machines to rotate, rotate at small angles, rotate at specified angles, and automatically track the target object to achieve active measurement.

[0003] The basic requirement for achieving the above functions is that the rotating mechanism needs to be highly stable. In existing turntable equipment, the persistent problem is the gap between the rotating mechanism and the rotating shaft, as well as the frictional force in the direction of gravity. The gap causes the rotating mechanism and the rotating shaft to be out of axis. When the rotating mechanism rotates, it will produce eccentric rotation, which will affect the rotational accuracy and stability of the entire turntable. The frictional force between the rotating mechanism components will also cause frictional damping in the rotation of the entire mechanism, which will increase the torque required by the motor and thus affect the rotational efficiency. Especially when subjected to load, the frictional force will intensify, making it impossible for the motor torque to overcome the frictional force, resulting in abnormal operation or failure to operate, and making the turntable rotation unstable.

[0004] The current effective solution is to add bearings. Bearings can withstand high friction while ensuring low friction and reducing rotational clearance. However, bearings are standard products with fixed dimensions and load capacities, which limits their application when dealing with customized turntables with specific size and load requirements. Utility Model Content

[0005] The technical problem to be solved by this invention is that in existing state equipment, the rotating mechanism has a large rotational friction and unstable rotation.

[0006] Therefore, this utility model provides a backlash-free turntable rotation structure.

[0007] The technical solution adopted by this utility model to solve its technical problem is:

[0008] A backlash-free rotary table rotating structure includes,

[0009] spindle, and

[0010] A bushing, which is fitted onto the main shaft and rotates relative to the main shaft;

[0011] A rotating platform, which is connected to a bushing;

[0012] A bracket is disposed between the main shaft and the bushing, and a plurality of balls are embedded in the bracket, wherein the balls abut against at least one of the main shaft and the bushing.

[0013] Furthermore, a base is provided at one end of the bracket, the base is sleeved on the main shaft, and a number of balls are also embedded on the end face of the base facing the bracket, the balls abutting against the end face of the bushing.

[0014] Furthermore, a number of balls on the bracket are arranged along the circumference of the bracket and distributed at both ends of the bracket.

[0015] Furthermore, the number of steel balls at both ends of the bracket is the same.

[0016] Furthermore, the ball bearings on the support are arranged in a spiral shape.

[0017] Furthermore, it also includes a gear transmission structure for driving the bushing to rotate, the gear transmission structure comprising:

[0018] Worm, and

[0019] Multiple transmission gears, all of which are coaxially connected to the bushing, and all of which mesh with the same worm gear;

[0020] A backlash elimination structure is disposed between adjacent transmission gears;

[0021] The backlash elimination structure includes a first elastic element. In two adjacent transmission gears, one transmission gear has a sliding groove arranged along its circumference, and the other transmission gear is connected to a limiting block located in the sliding groove. The first elastic element is disposed between one end face of the limiting block and the sliding groove, and the first elastic element deforms along the circumference of the transmission gear.

[0022] Furthermore, it also includes a driver for driving the worm gear to rotate.

[0023] Furthermore, an anti-kicking component is provided at the end of the worm gear away from the driver, which provides buffering and limiting for the worm gear's displacement along its axial direction.

[0024] Furthermore, the anti-kick assembly includes a mounting base and a second elastic element. The mounting base is disposed within the turntable, and a mounting groove is provided on the side of the mounting base facing the worm gear. The second elastic element is disposed within the mounting groove.

[0025] The beneficial effects of this invention are that it ensures the rotating mechanism and the rotation center are coaxial, while also providing a certain load-bearing capacity and minimizing backlash and runout to ensure uniform and stable movement between the gear and the worm gear meshing with it. To ensure the coaxiality of the central shaft of the bore-spindle fit, this device uses ball bearings instead of traditional bearings, meeting these requirements without considering the size limitations of traditional bearings. The ball bearing assembly bushing achieves an interference fit to eliminate backlash, allowing the main shaft and bushing to rotate relative to each other under the action of the ball bearing assembly. The bushing always rotates around the main shaft, and the ball design reduces frictional damping, enhancing the rotational stability and wear resistance of the turntable.

[0026] Furthermore, the steel balls and the first elastic element in the gear transmission structure generate misaligned teeth, which makes the coaxially connected adjacent gears mesh tightly with the worm and the driving gear, thus achieving the backlash elimination function. In this way, the meshing backlash and error generated by the two-stage gear transmission are canceled out, and the cumulative error is greatly reduced, thereby improving the transmission accuracy. This allows the turntable to achieve both improved rotational resolution and ensure angular accuracy and rotational stability. Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] Figure 1 This is a schematic diagram of the backlash-free rotary table structure in this utility model.

[0029] Figure 2 This is a structural diagram showing the positional relationship between the main shaft and the bushing in this utility model.

[0030] Figure 3 This is a structural schematic diagram showing the positional relationship between the spindle and the ball bearing assembly in this utility model.

[0031] Figure 4 This is a schematic diagram of the structure of the dense ball bearing assembly in this utility model.

[0032] Figure 5 This is a structural schematic diagram of different arrangements of the ball bearings on the bracket in this utility model.

[0033] Figure 6 This is a schematic diagram of the gear transmission structure in this utility model.

[0034] In the diagram: 1. Housing; 2. Rotating platform; 3. Main shaft; 4. Bushing; 5. Ball bearing assembly; 51. Bracket; 52. Base; 53. Ball bearing; 6. Gear transmission structure; 61. Worm gear; 62. First gear transmission assembly; 63. Transmission shaft; 64. First transmission gear; 65. Second transmission gear; 66. Limiting block; 67. First elastic element; 68. Rolling element; 69. Second elastic element; 7. Driver. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0036] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0037] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0038] A backlash-free rotary table structure includes a rotating platform 2, a housing 1, a main shaft 3, a bushing 4, a ball bearing assembly 5, and a gear transmission structure 6. The ball bearing assembly 5 is disposed between the main shaft 3 and the bushing 4. The rotating platform 2 is mounted on the housing 1. The main shaft 3 and the bushing 4 form a rotating shaft assembly, which is disposed inside the housing 1 and coaxially connected to the rotating platform 2. A driver 7 drives a worm gear 61 to rotate via a first gear transmission assembly 62. The worm gear 61 is engaged with a second gear transmission assembly, which in turn drives the rotating shaft to rotate.

[0039] The ball bearing assembly 5 includes a bracket 51, a base 52, and balls 53. The bracket 51 can be designed in any shape for radial and axial functions, and the material can be copper, plastic, steel, etc., offering high variability. In this embodiment, the bracket 51 is cylindrical and is sleeved on the spindle 3 between the spindle 3 and the bushing 4. The base 52 is integrally formed with the bracket 51 and is coaxially connected to one end of the bracket 51. Both the bracket 51 and the end face of the base 52 facing the bracket 51 are provided with receiving grooves for accommodating the steel balls. The steel balls are embedded in the receiving grooves. The arrangement of the receiving grooves on the bracket 51 and the base 52 is not limited. The receiving grooves on the bracket 51 can be arranged in a spiral shape, or they can be arranged circumferentially on the bracket 51 and arranged in multiple layers along the axial direction of the bracket 51. The receiving grooves on the base 52 can be circumferentially arranged on the end face of the base 52.

[0040] Specifically, such as Figure 5 As shown in small figure (a), when the spindle 3 is relatively long, to prevent the hole-shaft fit from tilting, the balls 53 can be arranged at both ends of the bracket 51. The number of balls 53 is adjusted according to the magnitude of the radial load. If the lower load is large, more balls are arranged; if the upper load is large, more balls are arranged; if the upper and lower loads are the same, more balls are arranged.

[0041] like Figure 5 As shown in small figure (b), when the balls 53 are spirally arranged on the bracket 51, the same number can achieve uniform load bearing on the upper, middle and lower parts of the shaft, greatly enhancing stability and load distribution. This allows every part of the shaft and hole to be supported by steel balls, which can greatly enhance the load capacity, especially suitable for cases where the shaft is relatively long.

[0042] Ball bearings (Type 53) are commonly used parts in the market. Based on manufacturing processes, ball bearings (Type 53) are categorized into ground steel balls, forged steel balls, and cast steel balls. Based on materials, they are classified as bearing steel balls, stainless steel balls, carbon steel balls, copper bearing steel balls, and alloy balls. Bearing steel balls are essential industrial components. Alloy steel balls are spherical iron alloy wear-resistant bodies made primarily of carbon, chromium, manganese, and molybdenum, produced through forging, spinning, rolling, and casting.

[0043] The ball bearing assembly 5 and bushing 4 can achieve an interference fit to eliminate clearance, and the main shaft 3 and bushing 4 can rotate relative to each other under the action of the ball bearing assembly 5. The bushing 4 always rotates around the main shaft 3. The design of the ball 53 also makes the friction damping small, which enhances the rotational stability and wear resistance of the turntable.

[0044] The gear transmission structure 6 includes a driver 7, a first gear transmission assembly 62, a second gear transmission assembly, and a worm gear 61. Specifically, the first gear transmission assembly 62 includes a driving gear, a first driven gear, and a second driven gear. The driving gear is coaxially connected to the output shaft of the driver 7. The first driven gear and the second driven gear are coaxially connected and mesh with each other through a transmission shaft 63. The transmission shaft 63 can be connected to the housing of the turntable. Both the first driven gear and the second driven gear mesh with the driving gear. A backlash elimination structure is provided between the first driven gear and the second driven gear.

[0045] The worm 61 is coaxially connected to the drive shaft 63. The axial direction of the worm 61 is parallel to the axial direction of the output shaft of the driver 7. The second gear transmission assembly includes a first transmission gear 64 and a second transmission gear 65. The first transmission gear 64 and the second transmission gear 65 are coaxially mounted on the bushing 4 of the turntable. The axial directions of the first transmission gear 64 and the second transmission gear 65 are perpendicular to the worm 61. Both the first transmission gear 64 and the second transmission gear 65 mesh with the worm 61. A backlash elimination structure is also provided between the first transmission gear 64 and the second transmission gear 65.

[0046] The backlash elimination structure includes two rolling elements 68 and a first elastic element 67. The first elastic element 67 is a spring. Taking the second gear transmission assembly as an example, the first transmission gear 64 is provided with multiple sliding grooves. The length direction of the sliding grooves is set along the circumference of the first transmission gear 64. The second transmission gear 65 is provided with a limiting block 66. The limiting block 66 is inserted into the sliding groove. The limiting block 66 divides the sliding groove into two installation spaces along the circumference of the first transmission gear 64. The backlash elimination structure is located in one installation space of the sliding groove. The two rolling elements 68 abut against the limiting block 66 and the end face of the sliding groove, respectively. The first elastic element 67 is set between the two rolling elements 68. The rolling elements 68 are set as balls 53.

[0047] When the first transmission gear 64 and the second transmission gear 65 rotate under the drive of the worm 61, the driven gear is subjected to the force of the ball 53 and the first elastic element 67, resulting in tooth misalignment. The meshing teeth of the first transmission gear 64 and the second transmission gear 65 mesh tightly with the worm 61, achieving the backlash elimination function. In this way, the meshing backlash and error generated by the two-stage gear transmission are canceled out, and the resulting cumulative error is greatly reduced. In this embodiment, the number of driven gears and transmission gears coaxially arranged between the gear transmissions is two. In other embodiments, the number of driven gears and transmission gears coaxially arranged is not limited, and this backlash elimination structure can be arranged between adjacent driven gears and transmission gears.

[0048] By reducing the meshing error between gear teeth through a backlash-eliminating structure, the transmission accuracy is greatly improved, ensuring consistent rotation of each tooth. For multiple gear drives, this also significantly reduces cumulative errors, allowing the turntable to achieve both improved rotational resolution and guaranteed angular accuracy. Because the meshing backlash between gear teeth is reduced, the space for forward and reverse rotation is also decreased, ensuring consistent angular accuracy in both directions and enhancing the turntable's stability.

[0049] The worm 61 may experience axial movement due to machining accuracy, assembly clearance, or axial movement generated by the motor spindle 3 itself. In this application, an anti-kick component is provided at the end of the worm 61 away from the first gear transmission assembly 62.

[0050] The anti-kick assembly includes a mounting base, a second elastic element 69, and a steel ball. The mounting base is connected inside the housing 1, and a mounting groove is provided on the side of the mounting base facing the worm 61. The second elastic element 69 is a spring, which is disposed in the mounting groove. A groove is provided on the end face of the worm 61 facing the mounting base, and the steel ball is located in the groove. Part of the steel ball protrudes from the groove and abuts against the spring. The diameter of the steel ball is larger than the inner diameter of the spring.

[0051] By utilizing the spring at the end of the worm 61 shaft, the axial movement of the worm 61 and the axial movement of the motor spindle 3 itself can be reduced, so that the worm 61 teeth always maintain a single direction of helical movement and always mesh with the teeth of the transmission gear in the direction of rotation.

[0052] Due to errors in the machining precision and assembly of the worm 61 and gear, the tooth thickness of each tooth in the worm 61 and gear varies. This can easily lead to jamming, seizing, or wear between the teeth. Springs provide elastic adjustment, allowing the worm 61 to slide slightly when jamming occurs, thus preventing seizing, seizing, or wear. Furthermore, because it is not a rigid transmission, the noise is greatly reduced.

[0053] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined by the scope of the claims.

Claims

1. A backlash elimination rotary table rotary structure, characterized by, include, Main spindle (3), and A bushing (4) is fitted on the main shaft (3) and rotates relative to the main shaft (3); Rotating platform (2), which is connected to bushing (4); A bracket (51) is disposed between the main shaft (3) and the bushing (4). A plurality of balls (53) are embedded in the bracket (51), and the balls (53) abut against at least one of the main shaft (3) and the bushing (4). A gear transmission structure (6) is used to drive the bushing (4) to rotate. The gear transmission structure (6) includes: Worm (61), and Multiple transmission gears, all of which are coaxially connected to the bushing (4), and all of which mesh with the same worm (61); A backlash elimination structure is disposed between adjacent transmission gears; The backlash elimination structure includes a first elastic element (67). In two adjacent transmission gears, one transmission gear has a sliding groove arranged along its circumference, and the other transmission gear is connected to a limiting block (66). The limiting block (66) is located in the sliding groove. The first elastic element (67) is disposed between the limiting block (66) and one end face of the sliding groove. The first elastic element (67) deforms along the circumference of the transmission gear.

2. The lost motion turntable rotation structure of claim 1, wherein One end of the bracket (51) is provided with a base (52), which is sleeved on the main shaft (3). The end face of the base (52) facing the bracket (51) is also embedded with a number of balls (53), which abut against the end face of the bushing (4).

3. The lost motion turntable rotation structure of claim 1, wherein A plurality of balls (53) on the bracket (51) are arranged along the circumference of the bracket (51) and distributed at both ends of the bracket (51).

4. The lost motion turntable rotation structure of claim 3, wherein The number of steel balls at both ends of the bracket (51) is the same.

5. The lost motion turntable rotation structure of claim 1, wherein The ball bearings (53) on the bracket (51) are arranged in a spiral shape.

6. The lost motion turntable rotation structure of claim 1, wherein It also includes a driver (7) for driving the worm (61) to rotate.

7. The lost motion turntable rotation structure of claim 6, wherein The end of the worm (61) away from the driver (7) is provided with an anti-kick component, which provides buffering and limiting for the displacement of the worm (61) along its axial direction.

8. The lost motion turntable rotation structure of claim 7, wherein, The anti-kick assembly includes a mounting base and a second elastic element (69). The mounting base is disposed inside the turntable, and a mounting groove is provided on the side of the mounting base facing the worm (61). The second elastic element (69) is disposed in the mounting groove.

Images