A high-precision turntable

Abstract

The present invention discloses a high-precision turntable, which includes a bearing platform, a turntable and a crank-slider driving mechanism; the turntable is rotatably installed on the bearing platform along its rotation center; the crank-slider driving mechanism is arranged between the bearing platform and the turntable and is used to drive the turntable to rotate. The crank-slider driving mechanism includes a linear motion module assembly, a rotary motion module assembly and a connecting rod assembly. The connecting rod assembly connects the linear motion module assembly and the rotary motion module assembly. The linear motion module assembly is connected to the bearing platform, and the rotary motion module assembly is connected to the turntable. The high-precision turntable provided by the present invention has a small corner range, high precision requirements, strong load-bearing capacity, high driving torque, and stable rotation, and is suitable for various occasions.

Description

Technical Field

[0001] The present invention relates to the technical field of conveying devices, in particular to the technical field of turntables, and specifically to a high-precision turntable. Background Art

[0002] At present, there are three common turntable structures: one is to convert the rotation of the servo motor into the rotation of the turntable through a worm gear; one is to convert the linear motion of the drive mechanism into the rotation of the turntable through a gear rack; the other is a direct-drive turntable, where the torque motor rotor is directly connected to the turntable to form a rotating part, the stator is connected to the fixed seat to form a stationary part, and a circular cross roller bearing is set between the rotating part and the stationary part. When working, the turntable is driven to rotate by the torque motor, and the circular grating is used as position feedback.

[0003] The first type of worm gear turntable, as the use time increases, the worm wheel is prone to wear, resulting in a decrease in the turntable accuracy. The servo motor is connected to the worm through a coupling and there is a gap in the worm gear. When rotating in the opposite direction, there is a large return gap.

[0004] The second type is the rack and pinion turntable. The turntable accuracy is limited by the manufacturing accuracy of the gears. At the same time, the gear meshing inevitably produces a large return clearance. When a servo motor is used to drive the rack, it is also necessary to add mechanical transmission components such as ball screws, belt drives and reducers, which bring about a large reverse clearance, reduce the system stiffness, and poor turntable stability.

[0005] The third type of direct-drive turntable has a high cost because its angular accuracy is limited by the resolution and diameter of the circular grating scale. Summary of the invention

[0006] The main purpose of the present invention is to provide a high-precision turntable, aiming to solve the problems of low precision and poor stability of existing turntables.

[0007] To achieve the above object, the present invention proposes a high-precision turntable.

[0008] A turntable is rotatably mounted on the support platform along its rotation center; and

[0009] The crank slider driving mechanism is arranged between the supporting platform and the turntable, and is used to drive the turntable to rotate. The crank slider driving mechanism includes a linear motion module assembly, a rotary motion module assembly and a connecting rod assembly. The connecting rod assembly connects the linear motion module assembly and the rotary motion module assembly. The linear motion module assembly is connected to the supporting platform, and the rotary motion module assembly is connected to the turntable.

[0010] Optionally, a linear guide rail is provided on the upper end surface of the bearing platform;

[0011] The linear motion module assembly includes an adapter plate, and a linear slider group is provided on the end face of the adapter plate close to the carrier table, and the linear slider group is slidably mounted on the linear guide rail.

[0012] Optionally, the high-precision turntable further includes a linear motor, the linear motor has a mover and a stator, the stator of the linear motor is fixedly mounted on the carrier table, and the mover of the linear motor is connected to the adapter plate.

[0013] Optionally, the high-precision turntable further includes a linear grating scale, and the linear grating scale is provided on the carrier table;

[0014] A first reference surface, a second reference surface and a third reference surface are formed on the upper end surface of the carrier table, and the first reference surface, the second reference surface and the third reference surface are parallel to each other in pairs, wherein:

[0015] The reference surface of the linear grating scale coincides with the first reference surface; and / or,

[0016] The reference surface of the linear guide rail coincides with the second reference surface; and / or,

[0017] The reference surface of the stator of the linear motor coincides with the third reference surface.

[0018] Optionally, the high-precision turntable further includes a reading head, and the reading head is provided on the adapter plate;

[0019] A first mounting surface, a second mounting surface and a third mounting surface are formed on the adapter plate, and the first mounting surface, the second mounting surface and the third mounting surface are parallel to each other in pairs or are located in the same plane, wherein:

[0020] The mounting surface of the linear slider group coincides with the first mounting surface; and / or,

[0021] The mounting surface of the mover of the linear motor coincides with the second mounting surface; and / or,

[0022] The mounting surface of the reading head coincides with the third mounting surface.

[0023] Optionally, a fourth mounting surface, a fifth mounting surface and a sixth mounting surface are formed on the carrier table, and the fourth mounting surface, the fifth mounting surface and the sixth mounting surface are parallel to each other in pairs or are located in the same plane, wherein:

[0024] The mounting surface of the linear grating scale coincides with the fourth mounting surface; and / or,

[0025] The mounting surface of the linear guide rail coincides with the fifth mounting surface; and / or,

[0026] The mounting surface of the linear motor stator coincides with the sixth mounting surface.

[0027] Optionally, two bosses are provided on the adapter plate. The two bosses are spaced along the second direction. The two side surfaces of each boss facing each other along the first direction are the fourth reference surface and the fifth reference surface respectively, where:

[0028] The reference surface of the linear slider group coincides with the fourth reference surface; and / or,

[0029] The reference surface of the linear motor mover coincides with the fifth reference surface; and / or,

[0030] The second direction and the first direction are perpendicularly arranged in the horizontal plane.

[0031] Optionally, a sixth reference surface is formed on the adapter plate. The sixth reference surface is parallel to the fourth reference surface and / or the fifth reference surface, where:

[0032] The reference surface of the reading head coincides with the sixth reference surface.

[0033] Optionally, the high-precision turntable further includes two arc-shaped guide rails. The two arc-shaped guide rails are correspondingly arranged at both ends of the bearing table.

[0034] Two groups of arc-shaped slider groups are provided on the end surface of the turntable close to the bearing table. Each arc-shaped slider group cooperates with each arc-shaped guide rail, so that the turntable rotates along its rotation center;

[0035] The rotary motion module assembly includes the two arc-shaped guide rails and two groups of arc-shaped slider groups.

[0036] Optionally, the bearing table has two opposite ends. A seventh mounting surface and a seventh reference surface are formed at each end, where:

[0037] The reference surface of the arc-shaped guide rail coincides with the seventh reference surface; and / or,

[0038] The mounting surface of the arc-shaped guide rail coincides with the seventh mounting surface.

[0039] Optionally, the connecting rod assembly includes:

[0040] A connecting rod body, and mounting holes are formed at both ends of the connecting rod body;

[0041] Two stepped screws. One of the stepped screws mounts the connecting rod body on the rotary motion module assembly through one of the mounting holes, and the other stepped screw mounts the other end of the connecting rod body on the linear motion module assembly through the other mounting hole.

[0042] Optionally, the connecting rod assembly further includes a deep groove ball bearing and a bearing retaining ring. The deep groove ball bearing is disposed in the mounting hole and sleeved on the stepped screw. A protrusion is formed on the end face of the bearing retaining ring facing the deep groove ball bearing, and the protrusion is filled between the deep groove ball bearing and the stepped screw.

[0043] In the high-precision turntable provided by the present invention, the bearing table is driven to rotate by a crank-slider driving mechanism. During the actual movement process, the linear motion module assembly moves linearly on the bearing table, drives the connecting rod assembly to move, and the connecting rod assembly then drives the turntable to rotate, thereby realizing the conversion of linear motion into rotational motion. Thereby, the bearing capacity of the bearing table is improved, the stiffness of the bearing table is increased, the angular resolution of the high-precision turntable is improved, the force on the turntable is optimized, and the rotational torque of the turntable is increased, so that the high-precision turntable can be applicable to occasions with large size, small angular range, high precision requirements, strong bearing capacity, high rotational torque, and stable rotation process; in addition, the crank-slider driving mechanism is adopted, which has the advantages of simple structure, convenient installation, low cost, reliable operation, small return error, and more compact structure. Description of the Drawings

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0045] Figure 1 It is a schematic structural diagram of an embodiment of the high-precision turntable provided by the present invention;

[0046] Figure 2 It is a schematic diagram of the principle of the high-precision turntable provided by the present invention;

[0047] Figure 3 For Figure 1 the schematic diagram of the mechanism of the bearing table in

[0048] Figure 4 For Figure 3 the enlarged schematic diagram of part of the structure in

[0049] Figure 5 For Figure 1 the schematic diagram of the structure of the turntable in

[0050] Figure 6 For Figure 1 the schematic diagram of the structure of the adapter plate in

[0051] Figure 7 ForFigure 1 Structural schematic diagram of the middle connecting rod assembly.

[0052] Explanation of the reference numerals in the attached drawings:

[0053]

[0054]

[0055] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the attached drawings. Specific embodiments

[0056] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the attached drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0057] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the attached drawings). If the specific posture changes, the directional indications will also change accordingly.

[0058] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0059] For a worm and worm gear type turntable, as the usage time of the turntable increases, the worm is prone to wear, resulting in a decline in the accuracy of the turntable. Moreover, the servo motor drive is connected to the worm through a coupling, and there is a clearance between the worm and worm gear. When rotating in the reverse direction, there is a large return clearance. For a rack and pinion type turntable, the accuracy of the turntable is limited by the manufacturing accuracy of the gear. At the same time, large return clearances are inevitably generated during gear meshing. When using a servo motor to drive the rack, mechanical transmission components such as ball screws, belt drives, and reducers need to be added, which brings a large reverse clearance, reduces the system stiffness, and the stability of the turntable is poor. For a direct drive type turntable, the angular accuracy of the turntable is limited by the resolution and diameter of the circular grating scale, and the cost is high.

[0060] In view of this, the present invention provides a high-precision turntable. Figures 1 to 7 This is an embodiment of the high-precision turntable provided by the present invention. The high-precision turntable provided by the present invention has a small angular range, high precision requirements, strong load-bearing capacity, high driving torque, and smooth rotation, and is suitable for various occasions. The following mainly describes the high-precision turntable with reference to specific drawings.

[0061] Please refer to Figure 1 and Figure 2 . The high-precision turntable 100 includes a bearing platform 1, a turntable 2, and a crank-slider drive mechanism 3. The turntable 2 is rotatably installed on the bearing platform 1 along its rotation center. The crank-slider drive mechanism 3 is arranged between the bearing platform 1 and the turntable 2 and is used to drive the turntable 2 to rotate. The crank-slider drive mechanism 3 includes a linear motion module assembly 31, a connecting rod assembly 32, and a rotary motion module assembly 33. The connecting rod assembly 32 connects the linear motion module assembly 31 and the rotary motion module assembly 33. The linear motion module assembly 31 is connected to the bearing platform 1, and the rotary motion module assembly 33 is connected to the turntable 2.

[0062] In the high-precision turntable 100 provided by the present invention, the bearing platform 1 is driven to rotate by the crank-slider drive mechanism 3. During the actual movement process, the linear motion module assembly 31 makes a linear motion on the bearing platform 1, drives the connecting rod assembly 32 to move, and the connecting rod assembly 32 then drives the turntable 2 to rotate, thereby realizing the conversion of linear motion into rotary motion, improving the load-bearing capacity of the bearing platform 1, increasing the stiffness of the bearing platform 1, improving the angular resolution of the high-precision turntable 100, optimizing the force on the turntable 2, and increasing the driving torque of the turntable 2, so that the high-precision turntable 100 can be applied to occasions with large size, small angular range, high precision requirements, strong load-bearing capacity, high driving torque, and smooth rotation process. In addition, by adopting the crank-slider drive mechanism 3, the structure is simple, the installation is convenient, the cost is low, the operation is reliable, the return error is small, and the structure is more compact.

[0063] Figure 2 This is the schematic diagram of the high-precision turntable 100 provided by the present invention (i.e., the crank-slider mechanism). Among them, the DE section (the ground bearing the crank-slider) is equivalent to the bearing platform 1 of the present invention, C (the slider in the crank-slider mechanism) is equivalent to the linear motion module assembly 31 of the present invention, the BC section (the connecting rod in the crank-slider mechanism) is equivalent to the connecting rod assembly 32 of the present invention, and the AB section (the crank in the crank-slider mechanism) is equivalent to the rotary motion module assembly 33 of the present invention. During actual movement, the slider C slides linearly along the DE section, driving the rotation of the BC section connecting rod, thereby realizing the rotation of the AB section crank. Among them, during the movement process, the horizontal distance a between the rotation center A and the slider C remains unchanged, thereby realizing the stable rotation of the high-precision turntable 100.

[0064] In this embodiment, please continue to refer to Figure 2 , when the thrust of the linear motor 4 is constant, the longer the crank (AB section), the greater the torque of the turntable 2 and the smaller the angular resolution value. For example, when the crank length AB is 334.56 mm, the connecting rod length BC is 65.6 mm, the angle α is 6.08°, and the angle β is 9.93°, assuming the slider moves 1 μm, the rotation angle is approximately 0.6″.

[0065] The connection method between the turntable 2 and the bearing platform 1 is not limited, as long as it can ensure that the turntable 2 can rotate on the bearing platform 1. Considering the stability of the rotation process, in this embodiment, the connection method of the guide rail slider is preferably adopted. Specifically, please refer to Figure 3 and Figure 5 , two arc-shaped guide rails 12 are respectively formed at both ends of the end face of the bearing platform 1 facing the turntable 2; two arc-shaped slider groups 21 are provided on the end face of the turntable 2 close to the bearing platform 1, and each arc-shaped slider group 21 cooperates with each arc-shaped guide rail 12, so that the turntable 2 rotates along its rotation center. Specifically, in this embodiment, the driving slider driving mechanism drives the turntable 2 to rotate, and the two arc-shaped slider groups 21 slide along the corresponding mutual guide rails, thereby realizing the stable rotation of the turntable 2. It should be noted that during the rotation of the high-precision turntable 100, the end face of the turntable 2 (i.e., the plane for carrying items) needs to always be in a plane (i.e., during the rotation process, the turntable 2 cannot be tilted), and the end face of the turntable 2 needs to be perpendicular to the rotation axis (i.e., the rotation center), so as to ensure the stability of the rotation process.

[0066] It should be noted that in this embodiment, considering the smoothness of transmission and avoiding jamming during the transmission process, the mounting surface of the arc-shaped guide rail 12 needs to be parallel to the mounting end surface on the carrier 1. Moreover, according to the design index requirements, the flatness of the mounting surface of the arc-shaped guide rail 12 needs to be controlled within a certain range (the specific range value is selected according to the actual situation and actual needs). At the same time, the mounting surfaces of the two sets of arc-shaped slider groups 21 are always in the same plane. Therefore, in this embodiment, please refer to Figure 4 , at both ends of the end surface of the carrier facing the turntable, a seventh reference plane i and a seventh mounting surface q are respectively formed. During the installation process, the reference plane of the arc-shaped guide rail coincides with the seventh reference plane i, and the mounting surface of the arc-shaped guide rail coincides with the seventh mounting surface q. Further, before installing the arc-shaped guide rail 12, a seventh reference plane i with cylindricity requirements needs to be machined on the carrier 1. During installation, the bottom surface of the arc-shaped guide rail 12 is attached to the seventh mounting surface q, and then the inner side of the arc-shaped guide rail 12 is closely attached to the seventh reference plane i, and the arc center of the arc-shaped guide rail 12 coincides with the rotation center of the carrier 1 to ensure that the rotation center remains unchanged when the turntable 2 rotates.

[0067] It should be noted that in the actual application process, the number of the arc-shaped guide rail 12 and the arc-shaped slider groups 21 is not limited and can be selected according to the specific situation and application occasion. Specifically, one set can be set, with the arc-shaped guide rail 12 arranged in the middle of the carrier 1 and the arc-shaped slider group 21 correspondingly arranged in the middle of the turntable 2; or the setting method of this embodiment can be referred to, with two sets of the arc-shaped guide rail 12 and the arc-shaped slider groups 21 respectively arranged at both ends of the carrier 1 and the turntable 2. Compared with the setting method of one set, the setting method of two sets is preferred in this embodiment. On the one hand, the load-bearing capacity of the high-precision turntable 100 can be improved by using the setting method of two sets, which is suitable for some large-size occasions. On the other hand, the rotation process is more stable by using two sets, which is suitable for occasions with high-precision requirements; the setting method of one set is suitable for some occasions with smaller size, lighter weight and lower precision requirements.

[0068] Further, the number of arc-shaped sliders in each arc-shaped slider group 21 is not limited. It can be one, two, three, or four. Considering the stability of the transmission process and avoiding the risk of jamming, it is preferred in this embodiment that each arc-shaped slider group 21 contains two arc-shaped sliders.

[0069] Furthermore, each of the arc-shaped sliders includes a slider body and a slider connecting plate. The upper and lower planes of the slider connecting plate need to be parallel to each other. During installation, the slider connecting plate is fixed to the end face of the turntable 2 close to the bearing table 1 by screws, and the arc-shaped slider is fixed to the slider connecting plate by screws. In this way, it can be ensured that the end face (i.e., the rotation plane) of the turntable 2 is always in a plane.

[0070] It should be noted that the advantages of using the arc-shaped guide rail 12 and the arc-shaped slider group 21 as the rotary bearing of the turntable 2 are as follows: it can increase the axial load of the turntable 2 and ensure the parallelism of the plane of the turntable 2 during rotation. At the same time, it can reduce the height dimension of the high-precision turntable 100.

[0071] In this embodiment, the turntable 2 (it should be noted that not the entire turntable 2 is a part of the rotary motion module assembly 33, but with the axis where the rotation center is located as the cut-off point, the connection line between the rotation center and the part of the link assembly 32 constitutes a part of the rotary motion module assembly 33), two arc-shaped guide rails 12 and two groups of arc-shaped slider groups 21 constitute the rotary motion module assembly 33.

[0072] The driving method of the linear motion module assembly 31 is not limited and can be selected according to the actual situation. It can be a synchronous motor, a linear motor 4, or a driving cylinder. Specifically, in this embodiment, the high-precision turntable 100 further includes a linear motor 4. The stator of the linear motor 4 is fixedly installed on the bearing table 1, and the mover of the linear motor 4 is connected to the adapter plate. Compared with other setting methods, the driving method using the linear motor 4 in this embodiment is more concise and does not require setting additional redundant structures (selecting a synchronous motor requires setting an additional conversion mechanism to convert the rotational force into a linear force, and selecting a driving cylinder also requires an additional air supply system).

[0073] Furthermore, in this embodiment, the linear motor 4 adopts a coreless linear motor 4, so that the cogging effect of the motor can be eliminated. In actual application, the mover of the coreless linear motor 4 is directly connected to the load to achieve direct drive of the load, and there are no mechanical transmission components (ball screw pair, rack and pinion pair, transmission belt, etc.) in the middle, simplifying the structure of the linear motion module assembly 31 and making the rotation motion of the turntable smoother and more accurate.

[0074] Further, in this embodiment, the linear motion module assembly 31 uses one linear guide rail 11 in cooperation with two linear sliders; using one linear guide rail 11 can make the structure of the high-precision turntable 100 more compact; at the same time, compared with one linear slider, using two linear sliders can ensure the correct installation of the adapter plate 311 on the linear slider group 313 by adjusting the distance between the two linear sliders, so as to ensure that the distance and parallelism between the reading head 6 and the grating scale, and between the mover of the linear motor 4 and the stator of the linear motor 4 are within the allowable error range, avoiding the situation of large motion errors and vibrations caused by too low structural rigidity when using one linear slider.

[0075] Please refer to Figure 3 、 Figure 4 and Figure 5 , the high-precision turntable 100 further includes a linear grating scale 5, and the linear grating scale 5 is arranged on the bearing platform 1; in this embodiment, the linear grating scale 5 is used to detect the moving distance of the linear slider group 313; specifically, in order to ensure the accuracy requirements of the high-precision turntable 100, a first reference surface b, a second reference surface c and a third reference surface d are formed on the upper end surface of the bearing platform 1, and the first reference surface b, the second reference surface c and the third reference surface d are parallel to each other in pairs; at the same time, the first reference surface b, the second reference surface c and the third reference surface d have a certain spatial position relationship (that is, the distance between every two reference surfaces meets the process requirements); in the actual installation process, the reference surface of the linear grating scale 5 coincides with the first reference surface b (that is, the reference surface of the linear grating scale 5 is in close contact with the first reference surface b and completely coincides); the reference surface of the linear guide rail 11 coincides with the second reference surface c (that is, the reference surface of the linear guide rail 11 is in close contact with the second reference surface c and completely coincides); the reference surface of the stator of the linear motor 4 coincides with the third reference surface d (that is, the reference surface of the stator of the linear motor 4 is in close contact with the third reference surface d and completely coincides); it should be noted that when the reference surface of the linear grating scale 5 is not parallel to the reference surface of the linear guide rail 11, due to a certain angle between the linear guide rail 11 and the linear grating scale 5, when the linear slider group 313 moves, the moving distance feedback by the grating scale is farther than the actual moving distance. When the reference surface of the linear guide rail 11 is not parallel to the reference surface of the stator of the linear motor 4, the mover of the linear motor 4 will generate a component force perpendicular to the moving direction, which is not conducive to accurately controlling the moving distance of the mover of the linear motor 4.

[0076] Further, please refer to Figure 3 、 Figure 5 and Figure 6, the high-precision turntable 100 further includes a reading head 6, and the reading head 6 is arranged on the adapter plate 311; in order to increase the linear movement distance, two stators of the linear motor 4 need to be connected in series during actual application; the installation positions of the two stators of the linear motor 4 are determined by the stator positioning holes of the linear motor 4 (the stator mounting holes of the linear motor 4 are provided on the carrier table 1 according to process requirements); when performing linear movement, the reading head 6 and the linear grating scale 5 need to maintain a certain distance, and during the whole process, the mover of the linear motor 4 always needs to be kept at the middle position of the permanent magnets of the stator of the linear motor 4. Therefore, the mounting surface of the linear grating scale 5, the mounting surface of the linear guide rail 11, and the mounting surface of the stator of the linear motor 4 need to be parallel to each other or in a reference plane, and a certain tolerance range is set for the distances of each reference plane according to the installation requirements of the reading head 6 and the linear motor 4. Specifically, during actual installation, a first mounting surface h, a second mounting surface j, and a third mounting surface k are formed on the adapter plate 311, and a fourth mounting surface m, a fifth mounting surface n, and a sixth mounting surface p are formed on the carrier table 1. The first mounting surface h, the second mounting surface j, and the third mounting surface k are parallel to each other in pairs or in the same plane. At the same time, the first mounting surface h, the second mounting surface j, and the third mounting surface k have a certain spatial position relationship (that is, the distance between every two mounting surfaces meets the process requirements); among them: the mounting surface of the linear slider group 313 coincides with the first mounting surface h; the mounting surface of the mover of the linear motor 4 coincides with the second mounting surface j; the mounting surface of the reading head 6 coincides with the third mounting surface k; the fourth mounting surface m, the fifth mounting surface n, and the sixth mounting surface p are parallel to each other in pairs or in the same plane. Among them: the mounting surface of the linear grating scale coincides with the fourth mounting surface m; the mounting surface of the linear guide rail coincides with the fifth mounting surface n; the mounting surface of the stator of the linear motor coincides with the sixth mounting surface p; at the same time, the fourth mounting surface m, the fifth mounting surface n, and the sixth mounting surface p have a certain spatial position relationship (that is, the distance between every two mounting surfaces meets the process requirements). During actual operation, the mounting surface of the linear slider group 313, the mounting surface of the mover of the linear motor 4, and the mounting surface of the reading head 6 are parallel to each other or in the same plane. The linear slider group 313 is installed on the bottom surface of the adapter plate 311, and the linear slider group 313 is close to the linear slider reference surface. The linear slider group 313 is slidably installed with the linear guide rail 11. Therefore, the spatial position relationship between the adapter plate 311 and the carrier of the arc guide rail 12 is determined.

[0077] Furthermore, please refer to Figure 6, two bosses 312 are provided on the adapter plate 311. The two bosses 312 are arranged at intervals along the second direction. The two side surfaces of each boss 312 arranged oppositely along the first direction are respectively the fourth reference plane e and the fifth reference plane f. In this embodiment, one of the purposes of setting the two bosses 312 is that both sides of the boss 312 serve as the reference plane of the linear slider group 313 and the reference plane of the mover of the linear motor 4 respectively. Through the width of the boss 312, the distance between the linear slider group 313 and the mover of the linear motor 4 is determined, so as to determine the relative position relationship between the mover of the linear motor 4 and the stator of the linear motor 4; another purpose is to ensure that the reference plane of the linear slider group 313 and the reference plane of the linear guide rail 11 are parallel to each other. The distance between the two bosses 312 needs to be as far as possible. If the distance between the two bosses 312 is too close, it will easily cause a certain angle between the reference plane of the linear slider group 313 and the reference plane of the linear guide rail 11 on the carrier 1, and then cause too large installation errors of the reading head 6 and the mover of the linear motor 4, affecting the linear motion accuracy.

[0078] Specifically, in the actual installation process, the reference plane of the linear slider group 313 coincides with the fourth reference plane e; the reference plane of the mover of the linear motor 4 coincides with the fifth reference plane f; the second direction and the first direction are perpendicularly arranged in the horizontal plane; a sixth reference plane g is formed on the adapter plate 311, and the sixth reference plane g is parallel to the fourth reference plane e and / or the fifth reference plane f. Among them, the reference plane of the reading head 6 coincides with the sixth reference plane g. That is, the reference plane of the reading head 6, the reference plane of the linear slider group 313, and the reference plane of the mover of the linear motor 4 are parallel to each other. The linear slider group 313 and the mover of the linear motor 4 are respectively installed on the first installation surface h and the second installation surface j, and are respectively close to the fourth reference plane e and the fifth reference plane f. At this time, the reading head 6, the linear slider group 313, and the mover of the linear motor 4 are all fixed on the adapter plate 311, and the relative position relationship is determined, so as to ensure that the distance between the reading head 6 and the grating scale is within the required range, and the moving direction of the reading head 6 is parallel to the reference plane of the linear grating scale 5; the mover of the linear motor 4 is at the correct installation position of the stator of the linear motor 4, and the moving direction of the mover of the linear motor 4 is parallel to the reference plane of the stator of the linear motor 4.

[0079] In the present invention, the high-precision turntable 100 converts the linear motion force into the rotational motion force, so it needs to be realized through the link assembly 32. Please refer to Figure 7, in this embodiment, the connecting rod assembly 32 includes a connecting rod body 321 and two stepped screws 322; mounting holes are formed at both ends of the connecting rod body 321; one of the stepped screws 322 mounts the connecting rod body 321 on the rotary motion module assembly 33 through one of the mounting holes, and the other stepped screw 322 mounts the other end of the connecting rod body 321 on the linear motion module assembly 31 through the other mounting hole. For the convenience of description, the two stepped screws 322 are respectively named the first stepped screw and the second stepped screw; taking the first stepped screw as an example for description, a stepped screw 322 mounting hole is formed on the adapter plate 311 (which needs to be machined in advance according to the installation process requirements), the first stepped screw is mounted on the stepped screw 322 mounting hole on the adapter plate 311, and the first stepped screw is tightened so that the reference surface of the first stepped screw is in contact with the top surface of the adapter plate 311. The installation method of the second stepped screw is the same as that of the first stepped screw, and details will not be repeated here. It should be noted that the advantage of using the stepped screw 322 for installation is that the stepped screw 322 combines the advantages of a shaft and a screw. Compared with using a shaft and a screw simultaneously, using the stepped screw 322 can make the structure of the connecting rod assembly 32 simpler and more reliable; compared with designing and machining a bearing rotating shaft and its installation structure, the stepped screw 322 has a lower cost.

[0080] Further, for the convenience of description, taking the first stepped screw as an example, the functions of the bearing retainer 324 and the deep groove ball bearing 323 are described. Please continue to refer to Figure 7, in this embodiment, the connecting rod assembly 32 further includes a deep groove ball bearing 323 and a bearing retaining ring 324. The deep groove ball bearing 323 is disposed in the mounting hole and sleeved on the stepped screw 322. A protrusion is formed on the end face of the bearing retaining ring 324 facing the deep groove ball bearing 323, and the protrusion is filled between the deep groove ball bearing 323 and the stepped screw 322. In this embodiment, in order to ensure that the reference surface of the first stepped screw can closely adhere to the top surface of the adapter plate 311, there are two bearing retaining rings 324, and the two bearing retaining rings 324 are located at both ends of the connecting rod body 321. At this time, the sum of the heights of the two bearing retaining rings 324 and the inner ring height of the deep groove ball bearing 323 is equal to the axial length of the first stepped screw; when the first stepped screw is tightened, the inner ring of the deep groove ball bearing 323 is pressed by the two bearing retaining rings 324, restricting the displacement of the deep groove ball bearing 323 in the axial direction of the first stepped screw, and the bearing retaining ring 324 located at the upper end restricts the upward movement distance of the connecting rod. By controlling the cooperation between the deep groove ball bearing 323, the connecting rod body 321 and the first stepped screw and the clearance of the deep groove ball bearing 323, the return error of the turntable is reduced; the setting method of the second stepped screw, the deep groove ball bearing 323 and the bearing retaining ring 324 is the same as that of the first stepped screw, and will not be elaborated here one by one.

[0081] Further, in actual application, when the adapter plate 311 bears a rotational moment, the linear motion module assembly 31 (i.e., the linear motor 4, the linear guide rail 11, the linear slider group 313 and the adapter plate 311) generates a deflection angle. The rotation center of the linear motion module assembly 31 is the mounting hole of the first stepped screw. Since the mounting hole of the first stepped screw on the adapter plate 311 is located between the two linear sliders, the deflection angle has almost no influence on the position of the first stepped screw in the linear motion direction, thereby ensuring that the rotation angle of the turntable is not affected.

[0082] It should be noted that before installing the connecting rod assembly 32, the movements between the turntable 2 and the linear motion module assembly 31 do not interfere with each other. Through a series of structures, the motion accuracy, stiffness, and load-bearing capacity of the turntable 2 and the linear motion module assembly 31 are ensured respectively; when the turntable 2 and the linear motion module assembly 31 are connected by the connecting rod assembly 32, at this time, the three form the high-precision turntable 100, and the linear motion is efficiently and reliably converted into the rotational motion of the turntable 2 through the connecting rod assembly 32.

[0083] Furthermore, the advantages of the high-precision turntable 100 provided by the present invention compared to turntables and direct-drive turntables using transmission structures such as worm gears or rack and pinions are as follows: The crank-slider drive mechanism 3 drives the rotating plane of the turntable 2 to have high parallelism, strong load-bearing capacity, high angular resolution, large torque, small backlash, and low cost. The connecting rod assembly 32 is composed of components such as the connecting rod body 321, the stepped screw 322, the deep groove ball bearing 323, and the bearing retainer 324. It has a simple structure, is easy to install, has low cost, and operates reliably. By controlling the cooperation between the deep groove ball bearing 323 and the connecting rod body 321 and the stepped screw 322 and the clearance of the deep groove ball bearing 323, the backlash error of the turntable is reduced; for the linear motion module assembly 31, by reasonably setting the installation surfaces and reference surfaces of the linear slider group 313, the reading head 6, the mover of the linear motor 4, the position of the installation holes of the stepped screw 322, the linear guide rail 11, and the number of the linear slider groups 313, the rigidity of the linear motion module assembly 31 is improved and the force on the slider of the linear guide rail 11 is optimized, ensuring the accuracy of linear motion, while reducing the overall size of the linear motion slider and making the structure more compact.

[0084] It should be noted that all the above-mentioned reference surfaces (i.e., the first reference surface b, the second reference surface c, the third reference surface d, the fourth reference surface e, the fifth reference surface f, the sixth reference surface g, and the seventh reference surface i) are processed according to the requirements of the processing technology, that is, their flatness and other requirements meet the processing technology. The purpose of doing so is to ensure that the accuracy of the high-precision turntable 100 meets the requirements.

[0085] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A high-precision turntable, characterized in that, Comprising: A bearing platform; A turntable, rotatably mounted on the bearing platform about its rotation center; And, A crank-slider drive mechanism, disposed between the bearing platform and the turntable, for driving the turntable to rotate. The crank-slider drive mechanism includes a linear motion module assembly, a rotary motion module assembly, and a connecting rod assembly. The connecting rod assembly connects the linear motion module assembly and the rotary motion module assembly. The linear motion module assembly is connected to the bearing platform, and the rotary motion module assembly is connected to the turntable; A linear guide rail is provided on the upper end surface of the bearing platform; The linear motion module assembly includes an adapter plate. A linear slider group is provided on the end surface of the adapter plate close to the bearing platform, and the linear slider group is slidably mounted on the linear guide rail; The high-precision turntable further includes a linear motor, which has a mover and a stator. The stator of the linear motor is fixedly mounted on the bearing platform, and the mover of the linear motor is connected to the adapter plate; The linear motor adopts a coreless linear motor; The linear motion module assembly includes two linear sliders; The connection point between the connecting rod assembly and the linear motion module assembly is located between the two linear sliders; The high-precision turntable further includes a linear grating scale, which is disposed on the bearing platform; A first reference surface, a second reference surface, and a third reference surface are formed on the upper end surface of the bearing platform. The first reference surface, the second reference surface, and the third reference surface are parallel to each other in pairs. Among them: The reference surface of the linear grating scale coincides with the first reference surface; and / or, The reference surface of the linear guide rail coincides with the second reference surface; and / or, The reference surface of the stator of the linear motor coincides with the third reference surface.

2. The high-precision turntable according to claim 1, wherein The high-precision turntable further includes a reading head, which is disposed on the adapter plate; A first mounting surface, a second mounting surface, and a third mounting surface are formed on the adapter plate. The first mounting surface, the second mounting surface, and the third mounting surface are parallel to each other in pairs or are located in the same plane. Among them: The mounting surface of the linear slider group coincides with the first mounting surface; and / or, The mounting surface of the mover of the linear motor coincides with the second mounting surface; and / or, The mounting surface of the reading head coincides with the third mounting surface.

3. The high-precision turntable according to claim 1, wherein A fourth mounting surface, a fifth mounting surface, and a sixth mounting surface are formed on the bearing platform. The fourth mounting surface, the fifth mounting surface, and the sixth mounting surface are parallel to each other in pairs or are located in the same plane. Among them: The mounting surface of the linear grating scale coincides with the fourth mounting surface; and / or, The mounting surface of the linear guide rail coincides with the fifth mounting surface; and / or, The mounting surface of the stator of the linear motor coincides with the sixth mounting surface.

4. The high-precision turntable according to claim 2, wherein Two bosses are provided on the adapter plate. The two bosses are spaced apart along the second direction. The two side surfaces of each boss opposite to each other along the first direction are respectively a fourth reference surface and a fifth reference surface. Among them: The reference surface of the linear slider group coincides with the fourth reference surface; and / or, The reference surface of the mover of the linear motor coincides with the fifth reference surface; and / or, The second direction and the first direction are perpendicularly arranged to each other in a horizontal plane.

5. The high-precision turntable according to claim 4, wherein A sixth reference plane is formed on the adapter plate, and the sixth reference plane is parallel to the fourth reference plane and / or the fifth reference plane, where: The reference plane of the reading head coincides with the sixth reference plane.

6. The high-precision turntable according to claim 1, wherein The high-precision turntable further includes two arc-shaped guide rails, and the two arc-shaped guide rails are correspondingly arranged at two ends of the bearing table. Two sets of arc-shaped slider groups are provided on the end surface of the turntable close to the bearing table, and each arc-shaped slider group cooperates with each arc-shaped guide rail, so that the turntable rotates along its rotation center. The rotary motion module assembly includes the two arc-shaped guide rails and two sets of arc-shaped slider groups.

7. The high-precision turntable according to claim 6, wherein, The bearing table has two opposite ends, and a seventh mounting surface and a seventh reference plane are formed at each end, where: The reference plane of the arc-shaped guide rail coincides with the seventh reference plane; and / or The mounting surface of the arc-shaped guide rail coincides with the seventh mounting surface.

8. The high-precision turntable according to claim 1, wherein, The connecting rod assembly includes: A connecting rod body, and mounting holes are formed at two ends of the connecting rod body. Two stepped screws, one of the stepped screws mounts the connecting rod body on the rotary motion module assembly through one of the mounting holes, and the other stepped screw mounts the other end of the connecting rod body on the linear motion module assembly through the other mounting hole.

9. The high-precision turntable according to claim 8, wherein The connecting rod assembly further includes a deep groove ball bearing and a bearing retaining ring. The deep groove ball bearing is arranged in the mounting hole and sleeved on the stepped screw. A protrusion is formed on the end surface of the bearing retaining ring facing the deep groove ball bearing, and the protrusion is filled between the deep groove ball bearing and the stepped screw.

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