Flexible suspension ball screw driving air floating platform

Abstract

The invention relates to the technical field of air floating platforms, in particular to a flexible suspension ball screw driving air floating platform. Aiming at the problems that the stability of an air floating guide rail is difficult to control due to small air film damping, the repeated positioning precision is insufficient in high-end application, the stability of a ball screw is good, the precision is inversely proportional to the speed, and the straightness is far lower than that of the air floating guide rail, the following technical scheme is provided: the air floating guide rail comprises a base; the movable platform is arranged on the top of the base in a sliding mode, the bottom of the movable platform is fixedly connected with two sets of symmetrically-arranged guide blocks, and the guide blocks are arranged in an L shape and are in sliding fit with the base; and the driving mechanism is mounted in the base, and is used for driving the moving platform to do linear motion and facilitating stable control and repeated positioning. The positioning precision of the platform is effectively improved, the movement stability is guaranteed, and the requirements of high-end application scenes for high precision, high stability and rapid movement of equipment are met.

Description

Technical Field

[0001] The present invention relates to the technical field of air-bearing platforms, and particularly to a flexible suspension ball screw-driven air-bearing platform. Background Art

[0002] In the field of precision motion control, air-bearing guides and ball screws are two key components widely used. The air-bearing guide forms an air film between the guide and the platform through a grinding process. This unique working mode endows the air-bearing guide with extremely high straightness. With this advantage, the air-bearing guide effectively eliminates many problems caused by contact friction of traditional guides, providing the possibility for high-precision motion control.

[0003] However, the air-bearing guide is not perfect. Due to the extremely small damping of the air film, in practical applications, its stable control becomes a major challenge. When a linear motor is used to drive the air-bearing platform, although the linear motor can provide a relatively direct driving force, limited by the low-damping characteristic of the air-bearing guide, the repeat positioning accuracy of the system can only reach about 300 nm. This accuracy level is difficult to meet the increasingly stringent requirements in some high-end application scenarios such as precision machining and optical detection that have extremely high requirements for positioning accuracy.

[0004] On the other hand, as another commonly used linear motion conversion device, the ball screw can efficiently convert the rotation of a servo motor into linear motion. Its significant advantage lies in its good stability and is widely used in many occasions with high requirements for motion stability. However, the ball screw has an undeniable limitation, that is, there is an inverse relationship between its accuracy and speed. When the lead of the ball screw is designed to be large, a relatively high motion speed can be achieved, but the accuracy will be correspondingly reduced at this time; when the lead is small, although the accuracy can be improved, the motion speed will drop significantly. In addition, due to inevitable errors in the manufacturing process of the ball screw, its straightness is much lower than that of the air-bearing guide. This disadvantage makes it difficult to directly apply the ball screw in the air-bearing platform applications with extremely high requirements for straightness. In view of this, the present invention proposes a flexible suspension ball screw-driven air-bearing platform. Summary of the Invention

[0005] The object of the present invention is to propose a flexible suspension ball screw-driven air-bearing platform for the problems in the background art that the air-bearing guide is difficult to stably control due to the small damping of the air film and the repeat positioning accuracy is insufficient in high-end applications, and the ball screw has good stability but there is an inverse relationship between accuracy and speed and the straightness is much lower than that of the air-bearing guide.

[0006] Technical solution of the present invention: A flexible suspension ball screw driven air-floating platform, including a base; a moving platform slidably arranged on the top of the base, two symmetrically arranged guide blocks are fixedly connected to the bottom of the moving platform, the guide blocks are L-shaped and are slidably matched with the base; a driving mechanism installed in the base, the driving mechanism is used to drive the moving platform to perform linear motion and facilitate stable control and repeated positioning.

[0007] Optionally, the driving mechanism includes two positioning seats fixedly connected to the base, a first lead screw is rotatably connected in the two positioning seats, a first threaded sleeve is threadedly connected to the first lead screw, a first moving block is fixedly connected to the outer circle of the first threaded sleeve, a first connecting frame is arranged outside the first moving block, the first connecting frame is in a "U" shape, a plurality of first flexible sheets are connected between the first moving block and the first connecting frame, a first mounting plate is installed on the top of the first connecting frame, and the first mounting plate is connected to the bottom of the moving platform.

[0008] Optionally, it further includes an adjustment component arranged between the driving mechanism and the moving platform, and the adjustment component is used to drive the moving platform to perform a small displacement.

[0009] Optionally, the adjustment component includes a servo motor installed on the top of the first mounting plate, a fixing plate is arranged on the servo motor, the fixing plate is fixedly connected to the servo motor, a second lead screw is fixedly connected to the output end of the servo motor, a second threaded sleeve is threadedly connected to the second lead screw, a second moving block is fixedly connected to the outer circle of the second threaded sleeve, a second connecting frame is arranged outside the second moving block, the second connecting frame is in a "U" shape, a plurality of second flexible sheets are connected between the second moving block and the second connecting frame, a second mounting plate is installed on the top of the second connecting frame, and the second mounting plate is connected to the bottom of the moving platform.

[0010] Optionally, a through hole is opened in the moving platform, and a flexible component is arranged in the through hole.

[0011] Optionally, the flexible component includes a mounting table arranged in the through hole, a plurality of third flexible sheets are fixedly connected between both sides of the mounting table and the inner wall of the through hole, and the mounting table is fixedly connected to the first mounting plate or the second mounting plate.

[0012] Optionally, the third flexible sheet is perpendicular to the first lead screw.

[0013] In summary, the present application includes at least one of the following beneficial technical effects:

[0014] The present invention effectively improves the positioning accuracy of the moving platform by means of coarse adjustment with the first lead screw and fine adjustment with the second lead screw, meeting the requirements of application scenarios with extremely high positioning accuracy requirements such as precision machining and optical detection;

[0015] Furthermore, the influence of the manufacturing error of the first lead screw is eliminated by the first flexible sheet, the influence of the manufacturing error of the second lead screw is eliminated by the second flexible sheet, and the influence of friction during movement on the positioning accuracy is eliminated by the third flexible sheet;

[0016] In summary, the present invention effectively improves the platform positioning accuracy, ensures the movement stability, and meets the requirements of high-precision, high-stability and fast movement of the equipment in high-end application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A structural schematic diagram of a flexible suspension ball screw driven air-floating platform is given;

[0018] Figure 2 It is a structural schematic diagram of the driving mechanism;

[0019] Figure 3 It is a structural schematic diagram of the adjustment component;

[0020] Figure 4 It is a structural schematic diagram of the flexible component;

[0021] Figure 5 It is a structural schematic diagram of the bottom of the flexible component.

[0022] REFERENCE MARKS:

[0023] 1, base;

[0024] 2, moving platform; 21, guide block; 22, through hole;

[0025] 3, driving mechanism; 31, positioning seat; 32, first lead screw; 33, first thread sleeve; 34, first moving block; 35, first connecting frame; 36, first flexible sheet; 37, first mounting plate;

[0026] 4, adjustment component; 41, servo motor; 42, fixing plate; 43, second lead screw; 44, second thread sleeve; 45, second moving block; 46, second connecting frame; 47, second flexible sheet; 48, second mounting plate;

[0027] 5, flexible component; 51, mounting table; 52, third flexible sheet. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention.

[0029] The components of the embodiments of the present invention that are typically depicted and shown in the accompanying drawings herein can be arranged and designed in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention.

[0030] All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Embodiment 1

[0034] As Figure 1 shown, a flexible suspension ball screw driven air bearing platform proposed by the present invention includes a base 1; a moving platform 2 slidably disposed on the top of the base 1. Two symmetrically arranged guide blocks 21 are fixedly connected to the bottom of the moving platform 2. The guide blocks 21 are L-shaped and slidably cooperate with the base 1. A gas film is formed by the gas ejected from the inner sides of the moving platform 2 and the guide blocks 21. This gas film can effectively reduce the friction force and ensure that the moving platform 2 performs high-precision linear motion along the base 1. This is the basic structure for the air bearing platform to achieve smooth movement and is relatively mature in the prior art, so no further elaboration will be made here.

[0035] Further, please refer to Figure 1 and Figure 2, the above-mentioned air-floating platform includes a driving mechanism 3 installed in the base 1. The driving mechanism 3 is used to drive the moving platform 2 to perform linear motion and facilitate stable control and repeated positioning. The driving mechanism 3 includes two groups of positioning seats 31 fixedly connected to the base 1. A first lead screw 32 is rotatably connected in the two groups of positioning seats 31. Through the positioning seats 31, the first lead screw 32 can maintain in-situ rotation, ensuring the stability of power transmission. A first threaded sleeve 33 is threadedly connected to the first lead screw 32. When the first lead screw 32 rotates, it drives the first threaded sleeve 33 to move along the length direction of the first lead screw 32, thereby converting the rotational motion into a linear motion. A first moving block 34 is fixedly connected to the outer circle of the first threaded sleeve 33. When the first threaded sleeve 33 moves, it drives the first moving block 34 to move synchronously. A first connecting frame 35 is arranged outside the first moving block 34. The first connecting frame 35 is arranged in a "U" shape. A plurality of groups of first flexible sheets 36 are connected between the first moving block 34 and the first connecting frame 35. The first flexible sheets 36 are horizontally arranged and perpendicular to the first lead screw 32. These first flexible sheets 36 have unique functions and can effectively eliminate the influence of the manufacturing error of the first lead screw 32 on the linear motion of the moving platform 2, making the motion of the moving platform 2 more stable and accurate. A first mounting plate 37 is installed on the top of the first connecting frame 35. The first mounting plate 37 is connected to the bottom of the moving platform 2. The first connecting frame 35 is fixed to the bottom of the moving platform 2 through the first mounting plate 37. Thus, when the first lead screw 32 rotates, it drives the moving platform 2 to move, realizing the stable driving of the driving mechanism 3 for the moving platform 2.

[0036] In this embodiment, when the air-floating platform is started, gas is ejected from the inner sides of the moving platform 2 and the guide blocks 21, forming an air film between them. The air film reduces the frictional force, enabling the moving platform 2 to perform high-precision linear motion on the top of the base 1 by means of the sliding fit between the guide blocks 21 and the base 1. This is the basic support part for the operation of the entire platform.

[0037] The external power source drives the first lead screw 32 to rotate in the positioning seats 31, and the positioning seats 31 ensure the stable in-situ rotation of the first lead screw 32. As the first lead screw 32 rotates, the first threaded sleeve 33 threadedly connected to it moves along the length direction of the first lead screw 32. The first threaded sleeve 33 drives the first moving block 34 fixedly connected to its outer circle to move synchronously. The first moving block 34 is connected to the "U"-shaped first connecting frame 35 through a plurality of groups of first flexible sheets 36 that are horizontally arranged and perpendicular to the first lead screw 32. The first flexible sheets 36 eliminate the influence of the manufacturing error of the first lead screw 32. Finally, the first mounting plate 37 on the top of the first connecting frame 35 connects it to the bottom of the moving platform 2, thereby driving the moving platform 2 to move linearly and completing the driving process of the driving mechanism 3 for the moving platform 2.

[0038] Embodiment 2

[0039] As Figure 3As shown in the figure, based on the first embodiment, it further includes an adjustment component 4 disposed between the driving mechanism 3 and the moving platform 2. The adjustment component 4 is used to drive the moving platform 2 to perform a small displacement. The adjustment component 4 includes a servo motor 41 installed on the top of the first mounting plate 37. When the first threaded sleeve 33 moves, it drives the servo motor 41 to move synchronously, so that the adjustment component 4 can follow the overall movement of the driving mechanism 3, facilitating the real-time adjustment of the moving platform 2. A fixing plate 42 is provided on the servo motor 41, and the fixing plate 42 is fixedly connected to the servo motor 41, so that the servo motor 41 is firmly fixed on the top of the first mounting plate 37, ensuring the stability of the servo motor 41 during operation. The output end of the servo motor 41 is fixedly connected to a second lead screw 43. After the servo motor 41 is started, it drives the second lead screw 43 to rotate. A second threaded sleeve 44 is threadedly connected to the second lead screw 43. When the second lead screw 43 rotates, it drives the second threaded sleeve 44 to move along the length direction of the second lead screw 43, realizing another conversion from rotational motion to linear motion. A second moving block 45 is fixedly connected to the outer circumference of the second threaded sleeve 44. When the second threaded sleeve 44 moves, it drives the second moving block 45 to move synchronously. A second connecting frame 46 is provided on the outside of the second moving block 45. The second connecting frame 46 is arranged in a "U" shape. A plurality of second flexible sheets 47 are connected between the second moving block 45 and the second connecting frame 46. The second flexible sheets 47 are horizontally arranged and perpendicular to the first lead screw 32. Their function is similar to that of the first flexible sheet 36, and is used to eliminate the influence of the manufacturing error of the second lead screw 43 on the linear motion of the moving platform 2, further improving the accuracy of the moving platform 2 during fine adjustment. A second mounting plate 48 is installed on the top of the second connecting frame 46. The second mounting plate 48 is connected to the bottom of the moving platform 2. The second connecting frame 46 is fixed to the bottom of the moving platform 2 through the second mounting plate 48. Thus, when the second lead screw 43 rotates, it drives the moving platform 2 to move.

[0040] At the same time, the accuracy of the second lead screw 43 is less than that of the first lead screw 32, so that it is convenient to drive the moving platform 2 to move to a rough position when the first lead screw 32 rotates, and then fine-tune the position of the moving platform 2 by rotating the second lead screw 43, ensuring that the movement of the moving platform 2 is rapid and the positioning is accurate, meeting the requirements for adjusting the position of the moving platform 2 under different accuracy requirements.

[0041] In this embodiment, when the driving mechanism 3 drives the first threaded sleeve 33 to move, the servo motor 41 installed on the top of the first mounting plate 37 moves synchronously. The servo motor 41 is fixed to the first mounting plate 37 by the fixing plate 42. When the servo motor 41 is started, the output end drives the second lead screw 43 to rotate. The second threaded sleeve 44 on the second lead screw 43 then moves along the length direction of the second lead screw 43, and the second threaded sleeve 44 drives the second moving block 45 with a fixed outer ring to move synchronously. The second moving block 45 is connected to the "U"-shaped second connecting frame 46 through multiple groups of second flexible sheets 47 that are horizontal and perpendicular to the first lead screw 32, eliminating the manufacturing error of the second lead screw 43. The second mounting plate 48 at the top of the second connecting frame 46 is connected to the bottom of the moving platform 2. When fine adjustment is required, the servo motor 41 drives the second lead screw 43. First, the first lead screw 32 brings the moving platform 2 to a rough position, and then the position of the moving platform 2 is precisely adjusted through the second lead screw 43 to meet the position adjustment under different precision requirements.

[0042] Embodiment Three

[0043] As Figure 4 and Figure 5 As shown in the above Embodiment Two, a through hole 22 is provided in the moving platform 2, and a flexible component 5 is arranged in the through hole 22. The flexible component 5 includes a mounting table 51 arranged in the through hole 22. Multiple groups of third flexible sheets 52 are fixedly connected between both sides of the mounting table 51 and the inner wall of the through hole 22. The third flexible sheets 52 are perpendicular to the first lead screw 32, and the second mounting plate 48 is fixedly connected to the bottom of the mounting table 51. Through the arrangement of the third flexible sheets 52, the influence of friction on the positioning accuracy during the movement of the second lead screw 43 driving the moving platform 2 can be effectively eliminated. During the micro-displacement adjustment process, the positioning of the moving platform 2 can be ensured to be accurate, further improving the positioning accuracy and stability of the entire air-floating platform.

[0044] In this embodiment, in the through hole 22 of the moving platform 2, both sides of the mounting table 51 are connected to the inner wall of the through hole 22 through multiple groups of third flexible sheets 52 that are perpendicular to the first lead screw 32, and the second mounting plate 48 is fixed to the bottom of the mounting table 51. When the second lead screw 43 in the adjustment component 4 drives the moving platform 2 to move, the third flexible sheets 52 eliminate the influence of the friction generated during the movement on the positioning accuracy, further improving the positioning accuracy of the moving platform 2 during micro-displacement adjustment and the stability of the entire air-floating platform.

[0045] Embodiment Four

[0046] As Figure 3 and Figure 5As shown in the figure, based on the above-mentioned first embodiment, a through hole 22 is provided in the mobile platform 2, and a flexible component 5 is arranged in the through hole 22. The flexible component 5 includes a mounting table 51 arranged in the through hole 22. A plurality of groups of third flexible sheets 52 are fixedly connected between both sides of the mounting table 51 and the inner wall of the through hole 22. The third flexible sheets 52 are perpendicular to the first lead screw 32, and the first mounting plate 37 is fixedly connected to the bottom of the mounting table 51. Through the arrangement of the third flexible sheets 52, the influence of friction on the positioning accuracy when the first lead screw 32 drives the mobile platform 2 to move is eliminated, ensuring accurate positioning when the driving mechanism 3 normally drives the mobile platform 2, and providing guarantee for improving the overall performance of the air-floating platform from different angles.

[0047] In this embodiment, inside the through hole 22 of the mobile platform 2, both sides of the mounting table 51 are connected to the inner wall of the through hole 22 by a plurality of groups of third flexible sheets 52 perpendicular to the first lead screw 32, and the first mounting plate 37 is fixed to the bottom of the mounting table 51. When the first lead screw 32 in the driving mechanism 3 drives the mobile platform 2 to move, the third flexible sheets 52 eliminate the influence of the friction generated during this process on the positioning accuracy, ensuring accurate positioning of the platform when the driving mechanism 3 normally drives the mobile platform 2 and improving the overall performance of the air-floating platform.

[0048] The above specific embodiments are merely several alternative embodiments of the present invention. Based on the technical solution of the present invention and the relevant revelations of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A flexible suspension ball screw driven air bearing platform, characterized in that, Comprising: A base (1); A moving platform (2) slidably disposed on the top of the base (1), two sets of symmetrically arranged guide blocks (21) are fixedly connected to the bottom of the moving platform (2), the guide blocks (21) are L-shaped and are slidably matched with the base (1); A driving mechanism (3) installed in the base (1), the driving mechanism (3) is used to drive the moving platform (2) to perform linear motion and facilitate stable control and repeated positioning.

2. The flexible suspension ball screw driven air floating platform according to claim 1, wherein The driving mechanism (3) includes two sets of positioning seats (31) fixedly connected to the base (1), a first lead screw (32) is rotatably connected between the two sets of positioning seats (31), a first thread sleeve (33) is threadedly connected to the first lead screw (32), a first moving block (34) is fixedly connected to the outer ring of the first thread sleeve (33), a first connecting frame (35) is arranged outside the first moving block (34), the first connecting frame (35) is in a "U" shape, a plurality of first flexible sheets (36) are connected between the first moving block (34) and the first connecting frame (35), a first mounting plate (37) is installed on the top of the first connecting frame (35), and the first mounting plate (37) is connected to the bottom of the moving platform (2).

3. The flexible suspension ball screw driven air-bearing platform according to claim 2, wherein, It further includes an adjustment assembly (4) disposed between the driving mechanism (3) and the moving platform (2), and the adjustment assembly (4) is used to drive the moving platform (2) to perform a small displacement.

4. A flexible suspension ball screw driven air bearing platform according to claim 3, characterized in that, The adjustment assembly (4) includes a servo motor (41) installed on the top of the first mounting plate (37), a fixing plate (42) is arranged on the servo motor (41), the fixing plate (42) is fixedly connected to the servo motor (41), the output end of the servo motor (41) is fixedly connected to a second lead screw (43), a second thread sleeve (44) is threadedly connected to the second lead screw (43), a second moving block (45) is fixedly connected to the outer ring of the second thread sleeve (44), a second connecting frame (46) is arranged outside the second moving block (45), the second connecting frame (46) is in a "U" shape, a plurality of second flexible sheets (47) are connected between the second moving block (45) and the second connecting frame (46), a second mounting plate (48) is installed on the top of the second connecting frame (46), and the second mounting plate (48) is connected to the bottom of the moving platform (2).

5. A flexible suspension ball screw driven air floating platform according to claim 2 or 4, characterized in that, A through hole (22) is formed in the moving platform (2), and a flexible assembly (5) is arranged in the through hole (22).

6. The flexible suspension ball screw driven air floating platform according to claim 5, characterized in that, The flexible assembly (5) includes a mounting table (51) arranged in the through hole (22), a plurality of third flexible sheets (52) are fixedly connected between both sides of the mounting table (51) and the inner wall of the through hole (22), and the mounting table (51) is fixedly connected to the first mounting plate (37) or the second mounting plate (48).

7. A flexible suspension ball screw driven air bearing platform according to claim 6, wherein The third flexible sheet (52) is perpendicular to the first lead screw (32).

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