CN112475945A

CN112475945A - Precise rotary worktable

Info

Publication number: CN112475945A
Application number: CN202011222658.9A
Authority: CN
Inventors: 周书兴; 唐露新; 黄盛庆
Original assignee: Guangzhou Institute of Technology
Current assignee: Guangzhou Institute of Technology
Priority date: 2020-11-05
Filing date: 2020-11-05
Publication date: 2021-03-12

Abstract

The invention discloses a precise rotary worktable, which comprises a shell, wherein the top of the shell is provided with an opening; a cavity is arranged in the shell; a base and a transmission assembly for driving the base to rotate are arranged in the cavity; the shell is provided with a driving device; the output end of the driving device penetrates through the shell to be in transmission connection with the transmission assembly; the top of the base extends out of an opening and is connected with a turntable which rotates synchronously with the base; the transmission assembly comprises a gear assembly and a worm block in transmission connection with the gear assembly; the base comprises a worm wheel block in meshed connection with the worm block; a plurality of clamping devices used for limiting the working state of the base are also arranged in the cavity; the plurality of clamping devices are uniformly arranged around the circumferential direction of the base; the clamping device comprises a butting block and a driving block for driving the butting block to butt against and separate from the base. The invention solves the problems of inaccurate adjustment, clamping and positioning of workpieces and low processing precision, and has the advantages of simple structure and high transmission efficiency.

Description

Precise rotary worktable

Technical Field

The invention relates to the field of numerical control machine tools, in particular to a precise rotary worktable.

Background

The working principle of the rotary worktable is that a large reduction ratio can be realized by utilizing worm and gear transmission. The standard worm gear pair is used for transmission, and the center distance between a worm gear and a worm is as follows: 0.5m (Z2+ q), while the existing rotary worktable, in order to facilitate the installation and debugging, the worm is installed in an eccentric sleeve, the eccentric distance of the eccentric sleeve is more than or equal to a modulus, namely more than or equal to 1m, the center distance between the eccentric sleeve and the worm wheel is the standard center distance 0.5m (Z2+ q) minus the actual eccentric distance of the eccentric sleeve, the worm is deviated to the direction far away from the center of the worm wheel during the installation, after the worm is axially installed in place, the eccentric sleeve is rotated by 180 degrees, the worm wheel is meshed with the worm, and then the circumferential position of the eccentric sleeve is fixed. Therefore, the original standard worm gear pair transmission has three errors accumulated, namely a manufacturing error of a worm wheel reference circle, a manufacturing error of a worm rod reference circle and a manufacturing error of a center distance between the worm wheel and the worm rod; the existing rotary worktable has the defects of low indexing precision, unstable precision and the like caused by accumulation of five errors, namely, an eccentric distance manufacturing error of an eccentric sleeve, a central offset error caused by a fit clearance between a worm and the eccentric sleeve, and the like besides the accumulation of the three errors. Typical or common prior art techniques are:

if CN201816052U discloses a high accuracy rotary table, including the base, the revolving stage, be equipped with the worm wheel on the revolving stage, be equipped with revolving stage locking handle on the base, the worm seat passes through locating pin and worm seat set screw and base tip fixed connection, the cylinder vernier passes through the fix screw fix on the seat hole coaxial with the worm, the calibrated scale is connected with the cylinder vernier, the hand wheel passes through hand wheel set screw and is connected with the calibrated scale, be equipped with the handle on the hand wheel, the worm passes through two double-row angular contact bearings to be fixed on the worm seat, install the adjusting pad between worm seat and the base tip, the worm both ends are ann has the end cover, ann has end cover set screw on the end cover, worm one end is connected with the transmission shaft through V type face clutch, be equipped with the spring on the transmission. The worm of the invention adopts a split structure, the meshing clearance between the worm and the worm wheel can be adjusted, the influence of the accumulation of manufacturing errors of various parts on the indexing precision of the rotary worktable is eliminated, and the processing difficulty of the parts is reduced. Another classic is like CN105583640A discloses a gyration is supported and is born weight of straight tooth transmission rotary worktable, including the base, the gyration is supported, main shaft aligning system, the workstation, straight tooth transmission and gap eliminating device, servo motor, arresting gear, supporting mechanism adopts rotary worktable to bear, rotary worktable accuracy control is by rotary worktable and main shaft aligning system joint control, drive arrangement adopts straight tooth gap eliminating mechanism, arresting gear adopts the braking of hydraulic braking circle. The invention has the advantages of high precision, durable and stable performance, strong bearing capacity, long service life and the like. Looking again at the prior art as US08230794B1 discloses that the table is provided with a clamping device having a movable element. The holding system has a top with a fibrous or pierceable material arranged on a table near the clamping means. The system employs at least one block having a working face and a connecting face. The working surface is adapted to oppose the movable element. The block has at least one connector on its attachment face for securing the clamp in position at the top against a clamping force from the clamping means. The connector includes a first hub and a second hub, each hub having a plurality of helix angles on one side thereof. The helical helix on the first hub spirals in a direction opposite the helical tip on the second hub. The connector also has a manually connectable connection between the hubs for rotating them in opposite directions to releasably connect to the fibrous or pierceable material of the top. The workpiece is placed between the block and the movable element. The clamping device is operated to clamp the workpiece between the movable element and the block.

In conclusion, through the mass search of the applicant, the rotary working table in the field at least has the problems of inaccurate adjustment, clamping and positioning of workpieces and low machining precision. Therefore, there is a need to develop or improve a precision rotary table.

Disclosure of Invention

The invention aims to provide a precise rotary worktable to solve the problems.

In order to achieve the purpose, the invention adopts the following technical scheme:

a precise rotary worktable is characterized by comprising a shell with an opening at the top; a cavity is arranged in the shell; a base and a transmission assembly for driving the base to rotate are arranged in the cavity; the shell is provided with a driving device; the output end of the driving device penetrates through the shell to be in transmission connection with the transmission assembly; the top of the base extends out of the opening and is connected with a turntable which rotates synchronously with the base; the transmission assembly comprises a gear assembly and a worm block in transmission connection with the gear assembly; the base comprises a worm wheel block in meshed connection with the worm block; a plurality of clamping devices used for limiting the working state of the base are further arranged in the cavity; the clamping devices are uniformly arranged around the circumference of the base; the clamping device comprises an abutting block and a driving block used for driving the abutting block to abut against and separate from the base.

Preferably, a plurality of clamping devices for limiting the working state of the base are further arranged in the cavity; the clamping devices are uniformly arranged around the circumference of the base; the clamping device comprises an abutting block and a driving block used for driving the abutting block to abut against and separate from the base.

Preferably, the gear assembly comprises a plurality of first gear blocks which are coaxially arranged; the first gear blocks are connected in series through bolts.

Preferably, the output end of the driving device is connected with a second gear block; the rotational axis of the second gear block is parallel to the rotational axis of the first gear block.

Preferably, the axis of rotation of the worm block is arranged coaxially with the axis of rotation of the first gear block.

Preferably, one end face of the turntable, which is far away from the base, is a working plane and is provided with a plurality of grooves; the turntable is provided with a mounting hole and a plurality of limiting holes arranged around the mounting hole on one end face facing the base.

Preferably, the base comprises a sleeve block with two open ends; a support block is sleeved in the sleeve block; a connecting shaft is inserted in the support block; one end of the connecting shaft extends out of the sleeve and is inserted in the mounting hole.

Preferably, a plurality of limiting blocks are arranged on one surface of the sleeve block, which is in contact with the turntable; the limiting block is inserted in the limiting hole.

Preferably, the outer surface of the sleeve block is provided with a clearance groove; the worm wheel block is arranged in the clearance groove.

Preferably, a plurality of mounting seats for mounting the transmission assembly are further arranged in the cavity.

The beneficial effects obtained by the invention are as follows:

1. the circular feeding mechanism is used for realizing circular feeding motion and indexing motion, and can complete the processing of various complex profiles by being linked with the X, Y, Z shaft.

2. The invention is mainly used for a numerical control boring machine and a milling machine, the working rotation angle of the numerical control boring machine and the milling machine is 360 degrees, the driving device drives the turntable to rotate, the accurate angular displacement or automatic indexing of the turntable is completed by the driving of the driving device, a workbench is required to be locked when the angular displacement or indexing movement is completed, and then the measurement or processing is carried out on the part. When box parts are machined, the rotary table can rotate, so that the work of repeated clamping, repeated tool changing and the like is omitted, and errors caused by human factors are reduced. Due to the indexing function of the turntable, the turntable can be used for machining in multiple stations, such as drilling, expanding, hinging, tapping and the like, and the machining has a series of action processes.

3. The invention solves the problems of inaccurate adjustment, clamping and positioning of workpieces and low processing precision.

Drawings

The invention will be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the embodiments. Like reference numerals designate corresponding parts throughout the different views.

FIG. 1 is a schematic structural diagram of a precision rotary table according to embodiments 1-2 of the present invention;

FIG. 2 is a second schematic structural diagram of a precision rotary table in embodiments 1-2 of the present invention;

FIG. 3 is a schematic diagram of an internal structure of a precision rotary table according to embodiments 1-2 of the present invention;

FIG. 4 is a second schematic view of an internal structure of a precision rotary table in embodiments 1-2 of the present invention;

FIG. 5 is a schematic diagram of an internal structure of a precision rotary table according to embodiments 1-2 of the present invention;

FIG. 6 is a top view of a base of a precision rotary table according to embodiments 1 to 2 of the present invention;

FIG. 7 is a cross-sectional view A-A of FIG. 6;

FIG. 8 is a third schematic structural diagram of a precision rotary table in embodiments 1-2 of the present invention.

Description of reference numerals: 1-a shell; 2-a cavity; 3-a base; 4-a transmission assembly; 5-a drive device; 6, rotating a disc; 7-a gear assembly; 71-a first gear piece; 8-a worm block; 9-a worm gear block; 10-a clamping device; 101-a butt block; 102-a drive block; 11-a second gear block; 12-a groove; 13-a sleeve; 14-a support block; 15-a connecting shaft; 16-mounting seat.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to embodiments thereof; it should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Other systems, methods, and/or features of the present embodiments will become apparent to those skilled in the art upon review of the following detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims. Additional features of the disclosed embodiments are described in, and will be apparent from, the detailed description that follows.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, but it is not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and are not to be construed as limiting the present patent, and the specific meaning of the terms described above will be understood by those of ordinary skill in the art according to the specific circumstances.

The first embodiment is as follows:

a precision rotary table as shown in fig. 1 to 8, which comprises a housing 1 with an opening at the top; a cavity 2 is arranged in the shell 1; a base 3 and a transmission assembly 4 for driving the base 3 to rotate are arranged in the cavity 2; the shell 1 is provided with a driving device 5; the output end of the driving device 5 penetrates through the shell 1 to be in transmission connection with the transmission assembly 4; the top of the base 3 extends out of the opening and is connected with a turntable 6 which rotates synchronously with the base 3; the transmission assembly 4 comprises a gear assembly 7 and a worm block 8 in transmission connection with the gear assembly 7; the base 3 comprises a worm wheel block 9 which is in meshed connection with the worm block 8; the cavity 2 is also internally provided with 2 clamping devices 10 for limiting the working state of the base 3; 2 of the clamping devices 10 are uniformly arranged circumferentially around the base 3; the clamping device 10 includes an abutting block 101 and a driving block 102 for driving the abutting block 101 to abut against and separate from the base 3.

As shown in fig. 3, in order to eliminate the dead zone (idle stroke) and improve the transmission precision, the gear assembly 7 in this embodiment 1 includes 2 first gear blocks 71 coaxially arranged; 2 of the first gear blocks 71 are connected in series by bolts.

As shown in fig. 3, the output end of the driving device 5 is connected with a second gear block 11; the rotation axis of the second gear block 11 is parallel to the rotation axis of the first gear block 71; the axis of rotation of the worm block 8 is arranged coaxially with the axis of rotation of the first gear block 71.

As shown in fig. 2 and 5, in order to ensure that the base 3 is better connected with the fixed turntable 6 and that the turntable 6 and the base 3 rotate synchronously, an end surface of the turntable 6 far away from the base 3 in this embodiment 1 is a working plane and is provided with a plurality of grooves 12, and the grooves 12 are T-shaped grooves, so that chip cleaning, chip removal and fixture installation are easy; the turntable 6 is provided with a mounting hole and a plurality of limiting holes arranged around the mounting hole on one end face facing the base 3.

In addition, as shown in fig. 6 to 7, in order to cooperate with the installation and rotation of the turntable 6, the base 3 in this embodiment 1 includes a sleeve block 13 with two open ends; a support block 14 is sleeved in the sleeve block 13; a connecting shaft 15 is inserted into the support block 14; one end of the connecting shaft 15 extends out of the sleeve 13 and is inserted into the mounting hole; a plurality of limiting blocks are arranged on one surface of the sleeve block 13, which is in contact with the rotary table 6; the limiting block is inserted in the limiting hole.

In order to drive the rotation of the rotary table 6 by the meshing transmission of the worm wheel block 9 and the worm block 8, a clearance groove is formed on the outer surface of the sleeve block 13 in the embodiment 1; the worm wheel block 13 is arranged in the clearance groove.

In addition, in order to ensure the stability of the transmission assembly 4 during the transmission process and prevent the displacement caused by vibration during the operation process, a plurality of mounting seats 16 for mounting the transmission assembly 4 are further arranged in the cavity 2 in the embodiment 1; moreover, this embodiment 1 is through the design the outline of base 3 is column structure, the outline of carousel 6 be discoid with work platform is last still to be equipped with the calibrated scale to the regulation of placing the work piece on carousel 6, clamping and location accuracy have been guaranteed, and the machining precision is high.

Example two:

a precision rotary table as shown in fig. 1 to 8, which comprises a housing 1 with an opening at the top; a cavity 2 is arranged in the shell 1; a base 3 and a transmission assembly 4 for driving the base 3 to rotate are arranged in the cavity 2; the shell 1 is provided with a driving device 5; the output end of the driving device 5 penetrates through the shell 1 to be in transmission connection with the transmission assembly 4; the top of the base 3 extends out of the opening and is connected with a turntable 6 which rotates synchronously with the base 3; the transmission assembly 4 comprises a gear assembly 7 and a worm block 8 in transmission connection with the gear assembly 7; the base 3 comprises a worm wheel block 9 which is in meshed connection with the worm block 8; the cavity 2 is also internally provided with 2 clamping devices 10 for limiting the working state of the base 3; 2 of the clamping devices 10 are uniformly arranged circumferentially around the base 3; the clamping device 10 includes an abutting block 101 and a driving block 102 for driving the abutting block 101 to abut against and separate from the base 3. The shell 1 comprises an upper shell with an opening at the top and an end cover covering the opening; the end cover is provided with an opening for the top of the base 3 to pass through.

The transmission ratio i2 of the worm gear transmission part formed by matching the worm wheel block 9 and the worm block 8 is 100, and the worm block 8 adopts a double-lead worm and carries out backlash elimination through a gradual tooth thickness form. The transmission part of the worm block 8 drives the base 3 to rotate, the rotating disc 6 synchronously rotates along with the rotation, and the transmission part of the gear assembly 7 performs speed reduction transmission to the worm block 6.

As shown in fig. 3, in order to eliminate the dead zone (idle stroke) and improve the transmission precision, the gear assembly 7 in this embodiment 2 includes 2 first gear blocks 71 coaxially arranged; 2 of the first gear blocks 71 are connected in series by bolts.

As shown in fig. 3, the output end of the driving device 5 is connected with a second gear block 11; the rotation axis of the second gear block 11 is parallel to the rotation axis of the first gear block 71; the rotation axis of the worm block 8 is arranged coaxially with the rotation axis of the first gear block 71; the transmission ratio i of the first gear block and the second gear block is 3, and the gear assembly 7 adopts a double-piece thin gear form to eliminate backlash, namely, eliminate dead zones (idle strokes) and improve transmission precision.

As shown in fig. 2 and 5, in order to ensure that the base 3 is better connected with the fixed turntable 6 and that the turntable 6 and the base 3 rotate synchronously, an end surface of the turntable 6 far away from the base 3 in this embodiment 2 is a working plane and is provided with a plurality of grooves 12, and the grooves 12 are T-shaped grooves, so that chip cleaning, chip removal and fixture installation are easy; the turntable 6 is provided with a mounting hole and a plurality of limiting holes arranged around the mounting hole on one end face facing the base 3.

In addition, as shown in fig. 6 to 7, in order to cooperate with the installation and rotation of the turntable 6, the base 3 in this embodiment 2 includes a sleeve block 13 with two open ends; a support block 14 is sleeved in the sleeve block 13; a connecting shaft 15 is inserted into the support block 14; one end of the connecting shaft 15 extends out of the sleeve 13 and is inserted into the mounting hole; a plurality of limiting blocks are arranged on one surface of the sleeve block 13, which is in contact with the rotary table 6; the limiting block is inserted in the limiting hole.

In order to drive the rotation of the rotary table 6 by the meshing transmission of the worm wheel block 9 and the worm block 8, a clearance groove is formed on the outer surface of the sleeve block 13 in the embodiment 2; the worm wheel block 13 is arranged in the clearance groove.

In addition, in order to ensure stability of the transmission assembly 4 in the transmission process and prevent displacement caused by vibration in the operation process, a plurality of mounting seats 16 for mounting the transmission assembly 4 are further arranged in the cavity 2 in the embodiment 2; moreover, this embodiment 1 is through the design the outline of base 3 is column structure, the outline of carousel 6 be discoid with work platform is last still to be equipped with the calibrated scale to the regulation of placing the work piece on carousel 6, clamping and location accuracy have been guaranteed, and the machining precision is high.

The 2 clamping devices in this embodiment 2 are arranged at an included angle of 40 degrees, and the working principle is as follows: when a user needs to process a workpiece placed on the turntable 6, the driving device 5 stops working, and the 2 driving blocks 102 respectively control the 2 abutting blocks 101 to lock the base 3; when a user needs to rotate the turntable 6, the 2 driving blocks 102 respectively control the 2 abutting blocks 101 to loosen the base 3, so that the turntable 6 can rotate. The driving block 102 is a hydraulic cylinder.

The drive device 5 is a 110-ST-M02030LFB type AC servo motor with rated torque T of 2.0Nm, rated current I of 4.0A, power of 0.6kw, and rotation speed of 3000 rpm. The incremental pulse encoder of the closed-loop servo system sends out pulse signals to act on the servo motor, so that the rotary table 6 rotates to a specified displacement angle, the circular grating in the spindle system measures the angular displacement and feeds the angular displacement back to the closed-loop system, and the pulse encoder is adjusted to send out corresponding pulse quantity to act on the servo motor to compensate the angular displacement, so that the positioning precision of the rotary table 6 is achieved.

The working principle of the embodiment 3 is as follows: the rotary worktable completes the angular displacement or automatic indexing of the rotary table 6 by a driving device 5, namely a driving mode of a servo motor, a transmission structure adopts a worm transmission and gear transmission mode, namely, the driving device drives a gear transmission part to reduce speed, then the gear transmission part drives a worm part to transmit so as to make the rotary table 6 rotate, and after the rotary table 6 stops rotating in place, the clamping device 10 locks the base to prevent the base 3 from rotating to drive the rotary table 6 to rotate and shift or swing, thereby realizing the precise processing of a workpiece by a cutter.

Wherein, in actual use, the rotary table diameter has the following specifications: specifications such as 315mm, 400mm, 500mm, 630mm, 800mm, 1000mm, 1200mm correspondingly have: 3. 4, 6, 8 and the like. The rotary table with the diameter larger than 630mm is usually used for medium and large machine tools, and the rotary table with the diameter smaller than 630mm is used for small machine tools. When designing the rotary worktable, the characteristics and the practicability of the machine tool need to be considered, and the rotary worktable with 500mm and 6 station numbers is selected in the design.

Although the invention has been described above with reference to various embodiments, it should be understood that many changes and modifications may be made without departing from the scope of the invention. That is, the methods, systems, and devices discussed above are examples. Various configurations may omit, substitute, or add various procedures or components as appropriate. For example, in alternative configurations, the methods may be performed in an order different than that described, and/or various components may be added, omitted, and/or combined. Moreover, features described with respect to certain configurations may be combined in various other configurations, as different aspects and elements of the configurations may be combined in a similar manner. Further, elements therein may be updated as technology evolves, i.e., many elements are examples and do not limit the scope of the disclosure or claims.

Specific details are given in the description to provide a thorough understanding of the exemplary configurations including implementations. However, configurations may be practiced without these specific details, for example, well-known circuits, processes, algorithms, structures, and techniques have been shown without unnecessary detail in order to avoid obscuring the configurations. This description provides example configurations only, and does not limit the scope, applicability, or configuration of the claims. Rather, the foregoing description of the configurations will provide those skilled in the art with an enabling description for implementing the described techniques. Various changes may be made in the function and arrangement of elements without departing from the spirit or scope of the disclosure.

It is intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. The above examples are to be construed as merely illustrative and not limitative of the remainder of the disclosure. After reading the description of the invention, the skilled person can make various changes or modifications to the invention, and these equivalent changes and modifications also fall into the scope of the invention defined by the claims.

Claims

1. A precise rotary worktable is characterized by comprising a shell with an opening at the top; a cavity is arranged in the shell; a base and a transmission assembly for driving the base to rotate are arranged in the cavity; the shell is provided with a driving device; the output end of the driving device penetrates through the shell to be in transmission connection with the transmission assembly; the top of the base extends out of the opening and is connected with a turntable which rotates synchronously with the base; the transmission assembly comprises a gear assembly and a worm block in transmission connection with the gear assembly; the base comprises a worm wheel block in meshed connection with the worm block.

2. A precision rotary table according to claim 1 wherein said cavity is further provided with a plurality of clamping means for limiting the operating condition of said base; the clamping devices are uniformly arranged around the circumference of the base; the clamping device comprises an abutting block and a driving block used for driving the abutting block to abut against and separate from the base.

3. The precision rotary table of claim 1 wherein the gear assembly comprises a plurality of first gear blocks coaxially disposed; the first gear blocks are connected in series through bolts.

4. A precision rotary table according to claim 3 wherein a second gear block is connected to the output of the drive means; the rotational axis of the second gear block is parallel to the rotational axis of the first gear block.

5. A precision rotary table according to claim 3 wherein the axis of rotation of the worm block is arranged coaxially with the axis of rotation of the first gear block.

6. The precision rotary table of claim 1, wherein an end surface of the turntable away from the base is a working plane and is provided with a plurality of grooves; the turntable is provided with a mounting hole and a plurality of limiting holes arranged around the mounting hole on one end face facing the base.

7. A precision rotary table according to claim 6 wherein the base comprises a sleeve block open at both ends; a support block is sleeved in the sleeve block; a connecting shaft is inserted in the support block; one end of the connecting shaft extends out of the sleeve and is inserted in the mounting hole.

8. The precise rotary worktable of claim 7, wherein a plurality of limiting blocks are arranged on the surface of the sleeve block contacting the rotary table; the limiting block is inserted in the limiting hole.

9. The precision rotary table of claim 7, wherein the outer surface of the sleeve block is provided with a clearance groove; the worm wheel block is arranged in the clearance groove.

10. A precision rotary table according to claim 1 wherein a plurality of mounting blocks are provided in the cavity for mounting the drive assembly.