A two-dimensional turntable bearing for use in astronomical telescopes

Abstract

This application relates to a two-dimensional turntable bearing for astronomical telescopes, comprising a first outer ring and an inner ring. The inner wall of the first outer ring has a circumferentially oriented rotating position, within which an axial rotating assembly and a radial rotating assembly are disposed. The axial rotating assembly includes a first ball assembly and a second ball assembly. The inner ring rotatably rests within the rotating position between the first ball assembly and the second ball assembly. The radial rotating assembly includes a plurality of cylindrical rollers that roll in cooperation with the first outer ring. When the inner ring is located within the rotating position, the outer wall of the inner ring along the circumferential direction abuts against the plurality of cylindrical rollers. This application improves the flexibility and operating speed of the astronomical telescope during operation.

Description

Technical Field

[0001] This application relates to the field of two-dimensional turntable bearing technology, and in particular to a two-dimensional turntable bearing for use in astronomical telescopes. Background Technology

[0002] Two-dimensional turntable bearings are the core mechanical components for precise observations in astronomical telescopes. As the load-bearing foundation, they must stably support the core loads such as the telescope tube and imaging system, withstand combined radial and axial forces, and ensure the rigidity and stability of the overall structure during observation. This prevents deformation caused by self-weight or external disturbances. Through the coordinated rotation of the azimuth axis (horizontal rotation) and the pitch axis (vertical pitch), the telescope can achieve pointing coverage of any target on the celestial sphere. When tracking the diurnal motion of celestial bodies, they can provide uniform and smooth rotation, avoiding the impact of mechanical vibration or lag on image quality. Ultimately, they provide reliable mechanical motion support for long-exposure and high-resolution observations.

[0003] In existing two-dimensional turntable bearings used in astronomical telescopes, a three-row cylindrical roller combination bearing structure with a YRT structure is adopted, including an outer ring, two inner rings, upper and lower rows of cylindrical rollers and corresponding cage assemblies, a set of cylindrical rollers and connecting bolts; the rings are provided with mounting holes, lifting holes, connecting holes and lubrication holes; this two-dimensional turntable bearing can withstand large bidirectional axial loads, radial loads and overturning moments, and adopts a preloaded negative clearance structure, which has the characteristics of high precision, high rigidity and compact structure.

[0004] However, the three-row cylindrical roller bearing with YRT structure has three rows of cylindrical rollers and a preloaded negative clearance structure, which results in continuous and large contact pressure between the rollers and the raceways of the raceways. This causes the bearing to have to overcome significant friction between the contact pairs during startup, resulting in a relatively large starting friction torque. At the same time, the large starting friction torque and continuous contact pressure limit the bearing's rotation speed, thus limiting its rotational flexibility and operating speed, and restricting its applicability in scenarios requiring rapid adjustment. Summary of the Invention

[0005] The purpose of this invention is to improve the flexibility and speed of rotation of astronomical telescopes during operation. This application provides a two-dimensional turntable bearing for astronomical telescopes.

[0006] To achieve the above objectives, this application provides a two-dimensional turntable bearing for astronomical telescopes, employing the following technical solution:

[0007] A two-dimensional turntable bearing for use in astronomical telescopes includes a first outer ring and an inner ring. The inner wall of the first outer ring has a circumferentially oriented rotating position. An axial rotating assembly and a radial rotating assembly are disposed within the rotating position. The axial rotating assembly includes a first ball assembly and a second ball assembly. The inner ring rotatably rests within the rotating position between the first ball assembly and the second ball assembly. The radial rotating assembly includes a plurality of cylindrical rollers. The plurality of cylindrical rollers roll in cooperation with the first outer ring. When the inner ring is located within the rotating position, the outer wall of the inner ring abuts against the plurality of cylindrical rollers along the circumferential direction.

[0008] Preferably, the inner wall of the rotating part that abuts against the cylindrical roller has a limiting groove along the circumference, and the height of the limiting groove and the height of the cylindrical roller are in a transition fit.

[0009] Preferably, the radial rotation assembly further includes a first cage, and a plurality of the cylindrical rollers are evenly distributed circumferentially along the first cage.

[0010] Preferably, the axial rotation assembly further includes a second cage and a third cage, the first ball assembly includes a plurality of first balls, the plurality of first balls being evenly distributed on the second cage, and the second ball assembly includes a plurality of second balls, the plurality of second balls being evenly distributed on the third cage.

[0011] Preferably, a second outer ring is provided on the first outer ring near the rotation position, and the inner diameter of the second outer ring is the same as the inner diameter of the first outer ring.

[0012] Preferably, a holding position is provided on the rotation position near the limiting groove, and the first retainer is located in the holding position.

[0013] Preferably, the inner ring extends integrally with a fixing part in the axial direction.

[0014] Preferably, the first retainer, the second retainer, and the third retainer are all made of copper.

[0015] Preferably, the first retainer has a stress relief opening.

[0016] Compared with the prior art, the present invention provides a two-dimensional turntable bearing for astronomical telescopes, which has the following advantages:

[0017] 1. This application adopts a method in which the inner ring rotates along the inside of the first outer ring, thereby improving the stability of the inner ring when rotating along the first outer ring. When the inner ring rotates along the rotation position, the frictional force generated between the inner ring and the first outer ring is distributed through the cooperation of the first ball assembly and the second ball assembly. Compared with the two-dimensional turntable bearing that uses cylindrical rollers to achieve rotation in the axial direction, this reduces the effective area of ​​the rolling frictional force between the inner ring and the first outer ring, which is beneficial to reducing the rolling frictional force between the upper and lower surfaces of the inner ring along the thickness direction and the rotation position, thereby reducing the frictional torque when the inner ring starts along the first outer ring. At the same time, the cooperation of several cylindrical rollers rotating radially along the first outer ring limits the radial rotation path of the inner ring, thereby improving the flexibility of rotation and the operating speed of the astronomical telescope during operation.

[0018] 2. The first cage defines the installation positions of several cylindrical rollers to avoid mechanical interference between two adjacent cylindrical rollers when they rotate along the limiting groove. At the same time, the retaining position defines the rotation path of the first cage with the cylindrical rollers installed along the rotation position to avoid axial runout of the first cage with the cylindrical rollers installed when it rotates along the rotation position.

[0019] 3. The second retainer limits the path of rotation of the first balls along the rotation position, and the second retainer limits the path of rotation of the second balls along the rotation position, so as to prevent the first balls and the second balls from falling off along the rotation position, and to ensure that the rolling friction force on the inner ring surface is in a balanced state when the inner ring rotates between the first balls and the second balls. Attached Figure Description

[0020] Figure 1 This is a cross-sectional structural schematic diagram of a two-dimensional turntable bearing used in an astronomical telescope, according to an embodiment of this application.

[0021] Figure 2 yes Figure 1 An enlarged schematic diagram of part A in a two-dimensional turntable bearing used in astronomical telescopes.

[0022] Figure 3 This is a schematic diagram of the structure of the second cage in a two-dimensional turntable bearing for an astronomical telescope, according to an embodiment of this application.

[0023] Figure 4 This is a top view schematic diagram of a two-dimensional turntable bearing used in an astronomical telescope, according to an embodiment of this application.

[0024] Figure 5 This is a cross-sectional schematic diagram of the first cage in a two-dimensional turntable bearing for an astronomical telescope, according to an embodiment of this application.

[0025] Figure 6This is a schematic diagram of the overall structure of a two-dimensional turntable bearing used in an astronomical telescope, according to an embodiment of this application.

[0026] Explanation of reference numerals in the attached drawings: 1. First outer ring; 2. Inner ring; 3. Rotation position; 4. Axial rotation assembly; 41. Second cage; 411. Mounting ring; 42. Third cage; 5. Radial rotation assembly; 51. Cylindrical roller; 52. First cage; 521. Stress relief opening; 522. Mounting position; 6. Limiting groove; 7. First ball; 8. Second ball; 9. Second outer ring; 10. Retaining position; 11. Fixing part; 111. Fixing hole; 12. Mounting hole; 13. Fixing bolt hole; 14. Connecting hole; 15. Radial oil injection hole; 16. Oil cup. Detailed Implementation

[0027] The terms "upper," "lower," "left," "right," "front," "rear," "side," "above," "below," "upper surface," and "lower surface," mentioned or potentially used in this specification, are defined relative to the structures shown in the accompanying drawings. The terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component; these are relative concepts and may vary depending on their location and usage. Furthermore, the phrase "several" is a quantitative term and can be added or subtracted according to design or usage requirements; it does not limit the specific number of any component. Therefore, these or other directions should not be interpreted as restrictive terms.

[0028] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0029] This application discloses a two-dimensional turntable bearing used in astronomical telescopes. (Refer to...) Figure 1 and Figure 2 as well as Figure 6 A two-dimensional turntable bearing for use in astronomical telescopes includes a first outer ring 1 and an inner ring 2. The inner wall of the first outer ring 1 has a circumferentially ...

[0030] Specifically, the outer contour of the first outer ring 1 is circular, and the rotation position 3 is formed by a recess from the inner wall of the first outer ring 1 to the edge of the first outer ring 1. The rotation position 3 is coaxial with the first outer ring 1.

[0031] Furthermore, the axial rotation assembly 4 also includes a second cage 41 and a third cage 42. The first ball assembly includes a plurality of first balls 7, which are evenly distributed on the second cage 41. The second ball assembly includes a plurality of second balls 8, which are evenly distributed on the third cage 42. The outer contours of the first balls 7 and the second balls 8 are spherical, and the diameters of the first balls 7 and the second balls 8 are the same. They can be made of steel to improve wear resistance.

[0032] The cooperation relationship between the second cage 41 and the plurality of first balls 7 is the same as the cooperation relationship between the third cage 42 and the plurality of third cages 42 and the plurality of second balls 8. For ease of explanation, the cooperation relationship between the second cage 41 and the plurality of first balls 7 will be described in detail below.

[0033] Furthermore, the outer contour of the second retainer 41 is arranged in a circular shape, and the thickness of the second retainer 41 is less than the diameter of the first ball 7. Three sets of mounting rings 411 are arranged at equal intervals along the axial direction to the edge of the second retainer 41. Each set of mounting rings 411 has several mounting holes 12 at equal intervals along the circumference. The diameter of the mounting holes 12 is in clearance fit with the diameter of the first ball 7. Several first balls 7 are installed one by one in the mounting holes 12 located on the mounting rings 411, so that the first balls 7 can roll smoothly along the second retainer 41.

[0034] It should be noted that the number of the first ball bearings 7 can be increased or decreased according to design requirements or the actual size of the second cage 41, and the number of mounting holes 12 is the same as the number of the first ball bearings 7, so that the first ball bearings 7 are installed in any mounting hole 12. Since they have the same function and are described in terms of quantity, their specific number is not limited here.

[0035] Therefore, in this embodiment, the axial rotation of the inner ring 2 is achieved by the cooperation of the first ball 7 and the second ball 8, forming a point contact between the inner ring 2 and the first outer ring 1. This reduces the static friction resistance experienced by the inner ring 2 during axial rotation and helps to eliminate the dead zone caused by static friction (i.e., the inner ring 2 cannot stay at the designated location). When a force is applied to the inner ring 2 to drive it to rotate along the first outer ring 1, compared to using cylindrical rollers 51 in both axial directions, the inner ring 2 can quickly stop rotating when the force disappears and the rotation of the inner ring 2 along the first outer ring 1 is suppressed. This avoids the problem of the inner ring 2 fretting again due to inertia and frictional torque after the suppression force disappears.

[0036] In addition, the cooperation of the first ball 7 and the second ball 8 reduces the contact area with the first outer ring 1 and the inner ring 2, which helps to reduce the heat generated by rolling friction.

[0037] Reference Figure 1 and Figure 2 The radial rotation assembly 5 also includes a first retainer 52, and a plurality of cylindrical rollers 51 are evenly distributed along the axial direction of the first retainer 52.

[0038] Specifically, the cylindrical roller 51 has a cylindrical outline. The first retainer 52 has mounting positions 522, the same number as the cylindrical roller 51, extending through its outer wall along the thickness direction. The spacing between any two adjacent mounting positions 522 is the same. The shape of the mounting positions 522 is adapted to the longitudinal cross-sectional outline of the cylindrical roller 51. The first retainer 52 limits the distance between two adjacent cylindrical rollers 51 when they rotate along the rotation position 3, so as to avoid mechanical interference between the two adjacent cylindrical rollers 51 during rotation, which would cause friction between the two adjacent cylindrical rollers 51.

[0039] Furthermore, a retaining position 10 is provided on the rotating position 3 near the limiting groove 6, and the first retainer 52 is located within the retaining position 10. The retaining position 10 is located at the limiting groove 6, and the diameter of the retaining position 10 is smaller than the diameter of the limiting groove 6. The width of the retaining position 10 and the first retainer 52 are in a clearance fit to reduce the probability of mechanical friction occurring between the first retainer 52 and the retaining position 10 when the first retainer 52 rotates along the rotating position 3.

[0040] Simultaneously, a limiting groove 6 is formed circumferentially on the inner wall of the rotating position 3 that abuts against the cylindrical roller 51. The height of the limiting groove 6 and the height of the cylindrical roller 51 are in a transition fit, where "transition fit" is a term used in the field of mechanical component assembly to describe a tolerance fit relationship. Therefore, during installation, several cylindrical rollers are first placed into the limiting groove 6 in sequence, and then the first retainer 52 is placed into the retaining position 10. The positions of the cylindrical rollers 51 located in the limiting groove 6 are adjusted so that any cylindrical roller 51 located in the limiting groove 6 is located in its corresponding mounting position 522.

[0041] Correspondingly, refer to Figure 5The first retainer 52 has a stress relief opening 521 with a width of 3mm-5mm. The stress relief opening 521 is formed by cutting any one of the first retainers 52, so that the first retainer 52 is in a non-closed loop state. When the several cylindrical rollers 51 roll along the limiting groove 6, the first retainer 52 will follow the several cylindrical rollers 51 to move along the rotation position 3. The first retainer 52 will be subjected to shear force applied by the several cylindrical rollers 51 along the tangential direction of the first retainer 52. At this time, the first retainer 52 will deform. Because the first retainer 52 has a stress relief opening 521, part of the shear force borne by the first retainer 52 when it rotates along the rotation position 3 will be released through the stress relief opening. When the first retainer 52 stops rotating along the rotation position 3, the shear force will disappear, so that the first retainer 52 can recover its deformation.

[0042] Therefore, since the first retainer 52 is in a non-closed-loop state, the width of the stress relief opening 521 will decrease when the first retainer 52 deforms. This is to avoid the problem that the shear force exerted on the first retainer 52 by several cylindrical rollers 51 is too large when the first retainer 52 rotates along the rotation position 3, which would cause the first retainer 52 to deform and thus cause mechanical friction between the first retainer 52 and the inner ring 2 or the first outer ring 1.

[0043] During the assembly process, several first balls 7 are firstly placed into the mounting holes 12 of the second retainer 41 in sequence, so that each mounting hole 12 on the second retainer 41 contains a first ball 7. Then, the second retainer 41 containing the first balls 7 is placed in the rotation position 3.

[0044] Subsequently, several cylindrical rollers 51 are sequentially placed into the limiting groove 6. Since the first retainer 52 has a stress relief opening 521, a force is applied to the first retainer 52 during the process of placing the first retainer 52 into the retaining position 10, thereby reducing the diameter enclosed by the first retainer 52, so as to facilitate the quick placement of the first retainer 52 into the retaining position 10.

[0045] Correspondingly, after the second retainer 41, on which the first ball bearing 7 is installed, is placed into the rotating position 3, and after the first retainer 52 confines the several cylindrical rollers 51 within the limiting groove 6, the inner ring 2 is placed into the rotating position 3. At this time, the surface of the inner ring 2 facing the second retainer 41 will be in contact with the several first ball bearings 7, and the outer wall of the inner ring 2 along the circumferential direction will be in contact with the several cylindrical rollers 51.

[0046] Furthermore, several second balls 8 are placed sequentially into the mounting holes 12 of the third retainer 42, so that each mounting hole 12 on the third retainer 42 contains a second ball 8. Finally, the third retainer 42 containing the second balls 8 is placed on the surface of the inner ring 2 away from the second retainer 41, at which point the inner ring 2 and several second balls 8 are in contact.

[0047] Reference Figure 1 and Figure 2 A second outer ring 9 is provided on the first outer ring 1 near the rotation position 3, and the inner diameter of the second outer ring 9 is the same as that of the second outer ring 9.

[0048] The outer ring 9 has a circular outline and the surface of the outer ring 9 that abuts against the first outer ring 1 is flat. After the complete assembly process, the outer ring 9 is placed on the first outer ring 1. At this time, several second balls 8 abut against the surfaces of the inner ring 2 and the second outer ring 9 respectively. The rotation position 3 is blocked by the second outer ring 9, so that the inner ring 2 can rotate stably along the coaxial axis of the first outer ring 1.

[0049] Furthermore, a number of fixing bolt holes 13 are provided circumferentially at the edge of the surface of the first outer ring 1, and a number of connecting holes 14, the same number as the fixing bolt holes 13, are provided circumferentially at the edge of the surface of the second outer ring 9. After the second outer ring 9 is fitted onto the first outer ring 1, the first outer ring 1 and the second outer ring 9 are fixedly connected by bolts through the cooperation of the fixing bolt holes 13 and the connecting holes 14.

[0050] The width of the rotating position 3 located between the first outer ring 1 and the second outer ring 9 is set to a, the thickness of the inner ring 2 is b, the diameter of the first ball 7 is c, and the diameter of the second ball 8 is d. After assembly, it is in the state of b+c+d=a, so that the inner ring 2 can rotate stably along the first outer ring 1.

[0051] Therefore, when the inner ring 2 rotates along the rotation position 3, the frictional force generated between the inner ring 2 and the first outer ring 1 is distributed by the first ball 7 and the second ball 8 through the cooperation of several first ball 7 and several second ball 8. Compared with the two-dimensional turntable bearing that uses cylindrical rollers 51 to achieve rotation in the axial direction, the effective area of ​​the rolling frictional force between the inner ring 2 and the first outer ring 1 is reduced. This is beneficial to reducing the rolling frictional force between the upper and lower surfaces of the inner ring 2 along the thickness direction and the rotation position 3, thereby reducing the frictional torque of the inner ring 2 when starting along the first outer ring 1. This is beneficial to improving the flexibility of rotation and the operating speed of the astronomical telescope during operation.

[0052] Furthermore, the axial rotation assembly 4 and the radial rotation assembly 5 are designed as independent modular structures to facilitate assembly and also to facilitate maintenance or replacement of the axial rotation assembly 4 and / or the radial rotation assembly 5.

[0053] Meanwhile, the first cage 52, the second cage 41, and the third cage 42 are all made of copper. The excellent thermal conductivity and wear resistance of copper play a positive guiding role in maintaining the service life of the first cage 52, the second cage 41, and the third cage 42.

[0054] Correspondingly, the inner ring 2 extends along the axial direction and is integrally formed with a fixing part 11. The diameter formed by the fixing part 11 is smaller than the inner diameter of the first outer ring 1, and the fixing part 11 has a fixing hole 111 through it along the thickness direction for connecting with the telescope tube and imaging system, so that the telescope tube and imaging system can stably follow the inner ring 2 to rotate along the first outer ring 1.

[0055] Reference Figure 4 The first outer ring 1 has a radial oil injection hole 15 extending from the outside to the rotation position 3. An oil cup 16 (an industrial lubrication device) is installed on the oil injection hole located on the outer wall of the first outer ring 1. Lubricating grease is injected into the rotation position 3 through the oil injection hole via the oil cup 16 to reduce the rolling friction of the inner ring 2 when it rotates along the first outer ring 1, and to play a positive guiding role in improving the smoothness of the inner ring 2's rotation along the first outer ring 1.

[0056] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A two-dimensional turntable bearing for use in astronomical telescopes, characterized in that: The device includes a first outer ring (1) and an inner ring (2). A circumferential rotation position (3) is provided on the inner wall of the first outer ring (1). An axial rotation assembly (4) and a radial rotation assembly (5) are provided within the rotation position (3). The axial rotation assembly (4) includes a first ball assembly and a second ball assembly. The inner ring (2) is rotatably supported within the rotation position (3) between the first ball assembly and the second ball assembly. The radial rotation assembly (5) includes several cylindrical rollers (51). These cylindrical rollers (51) roll in cooperation with the first outer ring (1). When the inner ring (2) is located within the rotation position (3), the inner ring (1)... 2) The outer wall along the circumferential direction abuts against several cylindrical rollers (51). The inner wall of the rotating position (3) that abuts against the cylindrical rollers (51) has a limiting groove (6) along the circumferential direction. The height of the limiting groove (6) is in a transition fit with the height tolerance of the cylindrical rollers (51). A retaining position (10) is provided on the rotating position (3) near the limiting groove (6). The radial rotating assembly (5) also includes a first retainer (52). Several cylindrical rollers (51) are evenly distributed along the circumference of the first retainer (52). The first retainer (52) is located inside the retaining position (10). The inner ring (2) is oriented towards the axis. The axial rotation assembly (4) is integrally formed with a fixing part (11). The axial rotation assembly (4) also includes a second retainer (41) and a third retainer (42). The first ball assembly includes a plurality of first balls (7), which are evenly distributed on the second retainer (41). The second ball assembly includes a plurality of second balls (8), which are evenly distributed on the third retainer (42). A second outer ring (9) is provided on the first outer ring (1) near the rotation position (3). The inner diameter of the second outer ring (9) is the same as the inner diameter of the first outer ring (1). The width of the rotation position (3) between (1) and the second outer ring (9) is a, the thickness of the inner ring (2) is b, the diameter of the first ball (7) is c, and the diameter of the second ball (8) is d. After assembly, it is in the state of b+c+d=a. The first retainer (52) is provided with a stress relief opening (521). When the first retainer (52) rotates along the rotation position (3), part of the shear force it bears will be released through the stress relief opening (521). When the first retainer (52) stops rotating along the rotation position (3), the shear force will disappear, so that the first retainer (52) can recover its deformation.

2. The two-dimensional turntable bearing for an astronomical telescope according to claim 1, characterized in that: The inner ring (2) extends along the axial direction and is integrally formed with a fixing part (11). The diameter formed by the fixing part (11) is smaller than the inner diameter of the first outer ring (1). The fixing part (11) has a fixing hole (111) through it along the thickness direction for connecting with the telescope tube and imaging system, so that the telescope tube and imaging system can stably follow the inner ring (2) to rotate along the first outer ring (1).

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