A composite feeding system

Abstract

The present invention discloses a composite feeding system, comprising a turntable and a feeding system, wherein the turntable comprises a worktable, a radial bearing, a rotating shaft, a lower thrust plate, an encoder and a torque motor, and the upper end face, the lower end face and the inner side face of the radial bearing are all provided with static pressure chambers; the feeding system comprises a base, a guide rail slider, a side guide rail bar and an upper guide rail bar, and the upper and lower end faces and the side faces of the guide rail slider are all provided with static pressure chambers, and the inner side wall of the guide rail slider is connected to the encoder mounting seat of the encoder, and the guide rail slider is driven by a driving assembly. The turntable of the present invention is connected to the guide rail slider through a radial bearing, and the stator of the torque motor is installed inside the guide rail slider, and the feeding system drives the turntable to perform linear motion, thereby forming a composite feeding system with an integrated high-precision turntable; the problems of poor precision of the existing composite feeding system and large size caused by the independent design of the turntable and the feed shaft are solved.

Description

Technical Field

[0001] The invention relates to the field of precision numerical control machining technology, in particular to a compound feeding system. Background Art

[0002] Composite feeding systems for precision or ultra-precision CNC machining equipment, composite multi-axis devices for precision and ultra-precision testing platforms. Composite feeding systems for precision and ultra-precision CNC machine tools (such as ultra-precision diamond turning machines, ultra-precision engraving and milling centers, ultra-precision machining centers and other precision machining equipment), and ultra-precision testing instruments (such as roundness meters, three-coordinate precision testing instruments, etc.) have the following main disadvantages:

[0003] 1. The rotary table mostly uses a servo motor as a driving element, a gear pair as a transmission element, and a rolling bearing as a supporting structure. The rolling bearing uses rolling elements, and the friction coefficient is larger than that of the hydrostatic support structure. The rotation accuracy and positioning accuracy of the turntable are relatively poor, which limits the application of the feed axis system in high-precision processing and testing equipment.

[0004] 2. Linear axes mostly use linear guides as guide elements of servo feed systems. The accuracy of this structure is mainly related to the accuracy of the linear guides, and the straightness of the servo feed system movement is limited.

[0005] 3. In the previous structure, even if the rotary table and linear axis adopt a hydrostatic structure, the rotary table and feed shaft are designed relatively independently, and the rotary table housing is directly installed on the feed shaft table, resulting in a large axial dimension of the entire structure and an overturning moment on the feed shaft support surface, which limits the development of the composite feed system towards integration and high precision. Summary of the invention

[0006] The object of the present invention is to provide a compound feeding system to solve the problems of poor precision and large size of the existing compound feeding system due to independent design of the turntable and the feeding shaft.

[0007] The present invention is achieved through the following technical solutions:

[0008] A composite feeding system comprises a turntable and a feeding system, wherein the turntable comprises a worktable, a radial bearing, a rotating shaft, a lower thrust plate, an encoder and a torque motor, wherein the upper end and the lower end of the rotating shaft are respectively connected to the worktable and the lower thrust plate, the radial bearing is arranged on the outer wall of the rotating shaft and between the worktable and the lower thrust plate, the encoder shaft of the encoder is connected to the bottom of the lower thrust plate, the rotor of the torque motor is connected to the bottom of the lower thrust plate, and the upper end face, the lower end face and the inner side face of the radial bearing are all provided with static pressure chambers; the feeding system comprises a base, a guide rail slider, a side guide Rails and upper rails, the upper end surface of the base is symmetrically provided with two side rails, the top of the side rails is connected with the upper rail, the guide slider is arranged on the inner side of the side rail and between the upper rail and the base, the upper end surface, the lower end surface and the inner side surface of the guide slider are provided with a static pressure cavity, the stator of the torque motor is connected to the guide slider, the top of the guide slider is connected to the radial bearing, the inner side wall of the guide slider is connected to the encoder mounting seat of the encoder, the encoder and the torque motor are both arranged on the inner side of the guide slider, and the guide slider is driven by a driving assembly.

[0009] The inner side of the side guide rail of the present invention specifically refers to the side opposite to the two side guide rails, and the inner side wall of the guide rail slider specifically refers to the side opposite to the two guide rail sliders.

[0010] In the present invention, the turntable uses the guide rail slider of the feed shaft as a fixed support seat, and directly fixes the radial bearing, the torque motor stator mounting seat, and the encoder mounting seat on the guide rail slider, fully utilizing the upper and lower bottom surfaces and the middle area of ​​the guide rail slider of the feed shaft for connection and fixation, and has a compact structure; this structure shortens the axial size of the hydrostatic support surface of the turntable and the feed shaft, and reduces the overturning moment; on the other hand, the feed shaft realizes the linear motion of the turntable through the guide rail slider, and solves the problems of poor precision of the existing composite feeding system and large size caused by the independent design of the turntable and the feed shaft.

[0011] Furthermore, the width of the workbench is consistent with the width of the base, the outer sides of the side guide bars and the upper guide bar are flush with the outer side of the base, and the workbench is arranged above the upper guide bar.

[0012] The outer side specifically refers to the side where two side guide rails or two upper guide rails face each other.

[0013] Furthermore, the encoder mounting seat is connected to the guide rail slider via a connecting plate, and two ends of the connecting plate are connected to the guide rail slider and the encoder mounting seat via bolts respectively.

[0014] Furthermore, the upper end surface of the base is recessed downward to form a mounting groove, the drive assembly is placed in the mounting groove, and the encoder mounting seat and the lower part of the torque motor are placed in the mounting groove.

[0015] Make full use of the mounting slots to further reduce space.

[0016] Furthermore, the upper and lower ends of the rotating shaft are respectively connected to the workbench and the lower thrust plate by bolts, the radial bearing is connected to the guide rail slider by bolts, and the upper and lower ends of the side guide bar are respectively connected to the upper guide bar and the base by bolts.

[0017] Furthermore, an inner U-shaped structure is formed between the side guide rails, the upper guide rail and the base, the guide rail slider is placed in the inner U-shaped structure, and the inner side of the guide rail slider protrudes from the inner side of the upper guide rail.

[0018] The inner U-shaped structure specifically refers to two U-shaped structures whose openings are arranged opposite to each other.

[0019] Furthermore, the rotating shaft, the worktable and the lower thrust plate constitute an outer U-shaped structure, the radial bearing is placed in the outer U-shaped structure, a static pressure chamber is formed between the upper end surface of the radial bearing and the lower end surface of the worktable, a static pressure chamber is formed between the lower end surface of the radial bearing and the upper end surface of the lower thrust plate, a static pressure chamber is formed between the inner hole of the radial bearing and the outer circle of the rotating shaft, and the lower end surface of the radial bearing is connected and contacted with the upper end surface of the guide rail slider.

[0020] The outer U-shaped structure specifically refers to two U-shaped structures whose openings are arranged facing each other.

[0021] Furthermore, a grating ruler is provided on the outer wall of the workbench in the feeding direction.

[0022] Furthermore, the driving assembly is provided with a protective cover.

[0023] Furthermore, the driving assembly is driven by a ball screw, a linear motor or a belt drive.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] 1. The turntable of the present invention adopts a hydrostatic bearing as a supporting structure and is equipped with a high-precision encoder, which can obtain very high indexing accuracy and meet the use requirements of precision and ultra-precision processing and testing equipment.

[0026] 2. The linear axis (feed system) of the present invention adopts a fluid hydrostatic guide rail, which has the characteristics of high rigidity and high straightness. At the same time, it is equipped with a high-precision grating ruler as a feedback link, which can obtain high positioning accuracy and repeat positioning accuracy; it meets the use requirements of precision and ultra-precision processing and testing equipment.

[0027] 3. The turntable and linear axis of the present invention are synchronously modeled and designed, with the guide rail slider of the feed shaft as the fixed support mechanism of the turntable, which shortens the axial dimension between the feed shaft and the turntable and reduces the overturning moment of the feed shaft. The entire feed system meets the requirements of compact structure and small overall size, and can be widely used in various high-performance CNC machine tools and high-precision detection equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0029] Figure 1 It is a schematic diagram of the overall structure of the integrated device;

[0030] Figure 2 A cross-sectional view of the integrated device.

[0031] Marks and corresponding parts names in the attached drawings:

[0032] 1-drive assembly, 2-base, 3-guide rail slider, 4-side guide bar, 5-upper guide bar, 6-workbench, 7-radial bearing, 8-rotating shaft, 9-lower thrust plate, 10-encoder shaft, 11-encoder, 12-encoder mounting seat, 13-torque motor, 14-connecting plate, 15-grating ruler, 16-protective cover. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0034] Embodiment 1:

[0035] like Figure 1 , Figure 2As shown, a composite feeding system includes a turntable and a feeding system, wherein the turntable includes a worktable 6, a radial bearing 7, a rotating shaft 8, a lower thrust plate 9, an encoder 11 and a torque motor 13, wherein the upper end and the lower end of the rotating shaft 8 are respectively connected to the worktable 6 and the lower thrust plate 9, the radial bearing 7 is arranged on the outer wall of the rotating shaft 8 and between the worktable 6 and the lower thrust plate 9, the encoder shaft 10 of the encoder 11 is connected to the bottom of the lower thrust plate 9, the rotor of the torque motor 13 is connected to the bottom of the lower thrust plate 9, the upper end face, the lower end face and the inner side face of the radial bearing 7 are all provided with static pressure chambers, the static pressure chambers are interconnected, the static pressure chambers have a gap of 10~20μm, and are fluid static pressure supports; the feeding system includes a base 2, a guide rail slider 3, a side guide rail bar 4 and an upper guide rail bar 5, the Two side guide rails 4 are symmetrically arranged on the upper end surface of the base 2, and the top of the side guide rail 4 is connected to the upper guide rail 5. The guide rail slider 3 is arranged on the inner side of the side guide rail 4 and between the upper guide rail 5 and the base 2. Static pressure chambers are arranged on the upper end surface, lower end surface and inner side surface of the guide rail slider 3, and each static pressure chamber is interconnected for fluid static pressure guide support. The stator of the torque motor 13 is connected to the guide rail slider 3, the top of the guide rail slider 3 is connected to the radial bearing 7, and the inner side wall of the guide rail slider 3 is connected to the encoder mounting seat 12 of the encoder 11. The encoder 11 and the torque motor 13 are both arranged on the inner side of the guide rail slider 3. The guide rail slider 3 is driven by a driving component 1, and the driving component 1 is driven by a ball screw drive, a linear motor drive or a belt drive to drive the guide rail slider 3 to move.

[0036] In this embodiment, the rotating shaft 8, the worktable 6 and the lower thrust plate 9 form axial and radial bearing support surfaces with the radial bearing 7, thereby forming a static pressure bearing capacity. The turntable adopts a fluid static pressure support, which has a small friction coefficient and a high rotation accuracy. The inner hole of the encoder 11 is connected to the encoder shaft 10, and the outer shell of the encoder 11 is connected to the encoder mounting seat 12. The encoder mounting seat 12 is fixed to the guide rail slider 3 by bolts to form a feedback system of the turntable, which can obtain excellent indexing accuracy. The static pressure oil enters through the side guide rail slider 3. Into the static pressure cavity, a static pressure support force is formed, that is, a static pressure support surface is formed between the side guide rail 4, the upper guide rail 5 and the base 2, with a small friction coefficient, and a high linear motion can be obtained; the turntable of this embodiment is connected to the guide rail slider 3 through the radial bearing 7, and the stator of the torque motor 13 is installed on the inner side of the guide rail slider 3. The feed system drives the turntable to move linearly, thereby forming a composite feed system with an integrated high-precision turntable; it solves the problem of poor precision of the existing composite feed system and large size caused by the independent design of the turntable and the feed shaft. The integrated device can be widely used in various high-precision machining centers and ultra-precision testing equipment.

[0037] Embodiment 2:

[0038] like Figure 1 , Figure 2 As shown, this embodiment is based on embodiment 1, the width of the workbench 6 is consistent with the width of the base 2, the outer sides of the side guide rails 4 and the upper guide rails 5 are flush with the outer side of the base 2, and the workbench 6 is arranged above the upper guide rails 5; the encoder mounting seat 12 is connected to the guide rail slider 3 through a connecting plate 14, and the two ends of the connecting plate 14 are respectively connected to the guide rail slider 3 and the encoder mounting seat 12 by bolts; the upper end surface of the base 2 is recessed downward to form a mounting groove, the drive assembly 1 is placed in the mounting groove, and the lower parts of the encoder mounting seat 12 and the torque motor 13 are placed in the mounting groove; the upper end and the lower end of the rotating shaft 8 are respectively connected to the workbench 6 and the lower thrust by bolts. The guide rail slider 3 is connected with the plate 9, the radial bearing 7 is connected with the guide rail slider 3 by bolts, and the upper and lower ends of the side guide rail bar 4 are respectively connected with the upper guide rail bar 5 and the base 2 by bolts; an inner U-shaped structure is formed between the side guide rail bar 4, the upper guide rail bar 5 and the base 2, and the guide rail slider 3 is placed in the inner U-shaped structure, and the inner side of the guide rail slider 3 protrudes from the inner side of the upper guide rail bar 5; the rotating shaft 8, the workbench 6 and the lower thrust plate 9 constitute an outer U-shaped structure, the radial bearing 7 is placed in the outer U-shaped structure, the upper end surface of the lower thrust plate 9 is flush with the upper end surface of the guide rail slider 3, and the lower end surface of the radial bearing 7 and the upper end surface of the lower thrust plate 9 are in contact with the upper end surface of the guide rail slider 3.

[0039] In this embodiment, the shape and size of each component are optimized to further reduce the overall volume and save space.

[0040] Embodiment 3:

[0041] like Figure 1 , Figure 2 As shown, this embodiment is based on the embodiment 1, the outer wall of the workbench 6 is provided with a grating ruler 15 in the feeding direction, and the driving assembly 1 is provided with a protective cover 16.

[0042] In this embodiment, the turntable uses a high-precision encoder 11 for feedback, and the linear drive measures the feedback through a grating ruler 15 to form a high-precision feedback system, thereby further improving the accuracy of the feedback.

[0043] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A composite feeding system, comprising a rotary table and a feeding system, characterized in that: The rotary table comprises a workbench (6), a radial bearing (7), a rotating shaft (8), a lower thrust plate (9), an encoder (11) and a torque motor (13); the upper end and the lower end of the rotating shaft (8) are respectively connected to the workbench (6) and the lower thrust plate (9); the radial bearing (7) is arranged on the outer wall of the rotating shaft (8) and between the workbench (6) and the lower thrust plate (9); the encoder shaft (10) of the encoder (11) is connected to the bottom of the lower thrust plate (9); the rotor of the torque motor (13) is connected to the bottom of the lower thrust plate (9); the upper end surface, the lower end surface and the inner side surface of the radial bearing (7) are all provided with static pressure chambers; the feeding system comprises a base (2), a guide rail slider (3), a side guide rail bar (4) and an upper guide rail bar (5); The upper end surface of the base (2) is symmetrically provided with two side guide rails (4), the top of the side guide rails (4) is connected to the upper guide rail (5), the guide rail slider (3) is arranged on the inner side of the side guide rail (4) and between the upper guide rail (5) and the base (2), the upper end surface, the lower end surface and the inner side surface of the guide rail slider (3) are all provided with static pressure chambers, the stator of the torque motor (13) is connected to the guide rail slider (3), the top of the guide rail slider (3) is connected to the radial bearing (7), the inner side wall of the guide rail slider (3) is connected to the encoder mounting seat (12) of the encoder (11), the encoder (11) and the torque motor (13) are both arranged on the inner side of the guide rail slider (3), and the guide rail slider (3) is driven by the driving assembly (1); The upper end surface of the base (2) is recessed downward to form a mounting groove, the drive assembly (1) is placed in the mounting groove, and the encoder mounting seat (12) and the lower part of the torque motor (13) are placed in the mounting groove; Wherein, the driving assembly (1) is provided in cooperation with a protective cover (16).

2. A compound feeding system according to claim 1, characterized in that: The width of the workbench (6) is consistent with the width of the base (2); the outer sides of the side guide rails (4) and the upper guide rails (5) are flush with the outer side of the base (2); and the workbench (6) is arranged above the upper guide rails (5).

3. A compound feeding system according to claim 1, characterized in that: The encoder mounting seat (12) is connected to the guide rail slider (3) via a connecting plate (14), and two ends of the connecting plate (14) are connected to the guide rail slider (3) and the encoder mounting seat (12) via bolts, respectively.

4. A compound feeding system according to claim 1, characterized in that: The upper end and the lower end of the rotating shaft (8) are connected to the workbench (6) and the lower thrust plate (9) respectively by bolts, the radial bearing (7) and the guide rail slider (3) are connected by bolts, and the upper end and the lower end of the side guide rail (4) are connected to the upper guide rail (5) and the base (2) respectively by bolts.

5. A compound feeding system according to claim 1, characterized in that: An inner U-shaped structure is formed between the side guide rails (4), the upper guide rail (5) and the base (2); the guide rail slider (3) is placed in the inner U-shaped structure; the inner side of the guide rail slider (3) protrudes from the inner side of the upper guide rail (5).

6. A compound feeding system according to claim 1, characterized in that: The rotating shaft (8), the worktable (6) and the lower thrust plate (9) form an outer U-shaped structure, and the radial bearing (7) is disposed inside the outer U-shaped structure.

7. A compound feeding system according to claim 1, characterized in that: The outer wall of the workbench (6) is provided with a grating ruler (15) in the feeding direction.

8. A compound feeding system according to any one of claims 1 to 7, characterized in that: The driving component (1) is driven by a ball screw, a linear motor or a belt drive.

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