Differential drive nano-positioning platform

Abstract

The utility model relates to positioning platform technical field especially difference driven nanometer positioning platform. It mainly aims at the positioning platform of adopting screw drive currently, and its adjustment accuracy depends on the lead of screw, but the minimum limit exists in the lead of screw, leads to the adjustment accuracy being limited, cannot satisfy the high accuracy application demand. In view of above -mentioned problem, the following technical scheme is presented, including base and the work platform located above the base, at least one group of guide rail assembly is set between the base and work platform, the difference driven mechanism is installed on the base, the difference driven mechanism includes the servo motor of movable arrangement, the coaxial rod is fixedly connected with servo motor output end, the coaxial rod is two section screw and is same, and the lead of different screw is composed. The utility model breaks through the minimum limit of screw lead and restricts the adjustment accuracy, can realize higher accuracy positioning adjustment, satisfies the demand of high accuracy application scene.

Description

Technical Field

[0001] This utility model relates to the field of positioning platform technology, and in particular to a differential-driven nano-positioning platform. Background Technology

[0002] The accuracy of positioning platforms plays a crucial role in the development of many cutting-edge technologies. Currently, widely used positioning platforms often employ lead screw drives to achieve precise adjustments. The principle of lead screw drive is to convert rotational motion into linear motion by rotating the lead screw, thereby driving the corresponding slider or worktable to adjust its position. Its adjustment accuracy largely depends on the lead screw's lead, that is, the distance the slider or worktable moves in the linear direction per revolution of the lead screw.

[0003] However, there is a minimum limit to the lead of the lead screw. From a manufacturing perspective, excessively small leads pose significant challenges in the machining process, making it difficult to achieve ideal standards in both cutting accuracy and forming quality control. Furthermore, lead screws with very small leads require extremely high torque from the drive unit in practical applications, which is difficult to meet with existing drive technologies. Moreover, lead screws with very small leads are prone to wear during long-term operation, leading to a decrease in accuracy. Due to the minimum limitation of the lead screw lead, the adjustment accuracy of lead screw-driven positioning platforms is severely restricted. Therefore, this invention proposes a differential-driven nano-positioning platform. Utility Model Content

[0004] The purpose of this invention is to address the problem that existing positioning platforms using lead screws in the background technology have adjustment accuracy that depends on the lead screw lead, but the lead screw lead has a minimum limit, which limits the adjustment accuracy and cannot meet the requirements of high-precision applications. The invention proposes a differential-driven nano-positioning platform.

[0005] The technical solution of this utility model is as follows: a differential-driven nano-positioning platform, including a base and a working platform located above the base; at least one set of guide rail assemblies disposed between the base and the working platform; a differential drive mechanism mounted on the base, the differential drive mechanism including a movably disposed servo motor, the output end of the servo motor being fixedly connected to a coaxial rod, the coaxial rod being composed of two lead screws with the same direction of rotation but different leads, the base and the working platform being threadedly engaged with a lead screw, and the displacement of the working platform being controlled by the difference in the leads of the two lead screws when the coaxial rod rotates.

[0006] Optionally, the guide rail assembly is mounted on the top of the base and is fixedly connected to the bottom of the work platform.

[0007] Optionally, the base has a mounting groove on its top, and the guide rail assembly is installed in the mounting groove.

[0008] Optionally, the differential drive mechanism further includes a mounting block fixedly connected to the servo motor, a slide rail fixedly connected to one side of the mounting block, a slider slidably connected in the slide rail, and the slider fixedly connected to the base or work platform.

[0009] Optionally, the coaxial rod is composed of a first lead screw and a second lead screw connected in a straight line on the same axis. The first lead screw and the second lead screw are arranged parallel to the guide rail assembly. A second threaded sleeve is threadedly connected to the second lead screw, and a fixing plate is fixedly connected to the outer ring of the second threaded sleeve.

[0010] Optionally, a first threaded sleeve is threadedly connected to the first lead screw, and a connecting plate is fixedly connected to the outer ring of the first threaded sleeve.

[0011] Optionally, the fixing plate and the connecting plate are fixedly connected to the base or the working platform, respectively.

[0012] Optionally, a displacement measuring unit is also included, which is disposed on the side of the base. The displacement measuring unit includes a grating ruler and a reading head. The grating ruler is installed on the side of the base, and the reading head is fixedly connected to the working platform.

[0013] Optionally, it also includes a set of bases and a working platform, guide rail assembly and differential drive mechanism disposed thereon, characterized in that the two sets of bases are orthogonally arranged, and the upper set of bases is fixedly connected to the top of the working platform.

[0014] Optionally, the servo motor is slidably coupled with the base or work platform.

[0015] In summary, this application includes at least one of the following beneficial technical effects:

[0016] This invention utilizes the differential drive mechanism to achieve minute movement of the work platform by cooperating with a first lead screw and a second lead screw with the same rotation direction but different leads. Compared with the traditional lead screw drive that relies on the adjustment of a single lead, this invention effectively avoids the limitation of minimum lead on accuracy and significantly improves positioning accuracy.

[0017] Furthermore, by using two sets of guide rail assemblies between the base and the work platform, compared to traditional ball guide rails, the rollers are arranged in a cross pattern, which can simultaneously withstand loads in multiple directions such as up and down, left and right, greatly reducing the impact of overturning moment during movement. The guide rail assembly has more contact points and is evenly distributed, which makes the friction coefficient of the work platform smaller and the operation more stable when moving, effectively reducing positioning errors caused by guide rail vibration or offset.

[0018] In summary, this invention overcomes the limitation of minimum lead screw pitch on adjustment accuracy, enabling higher precision positioning and adjustment to meet the needs of high-precision application scenarios. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the differential-driven nanopositioning platform.

[0020] Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure;

[0021] Figure 3 This is a schematic diagram of two sets of differentially driven nanopositioning platforms orthogonally arranged.

[0022] Figure label:

[0023] 1. Base; 11. Mounting slot; 12. Groove;

[0024] 2. Working platform; 3. Guide rail assembly; 4. Differential drive mechanism; 41. Slider; 42. Slide rail; 43. Mounting block; 44. Servo motor; 45. First lead screw; 46. Second lead screw; 47. Second threaded sleeve; 48. Fixing plate; 49. First threaded sleeve; 410. Connecting plate;

[0025] 5. Displacement measurement unit; 51. Synchronization plate. Detailed Implementation

[0026] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0027] The components of the present invention embodiments described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, 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 to illustrate selected embodiments of the invention.

[0028] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0029] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "coupling" 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 a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0031] Embodiment 1

[0032] As Figure 1 shown, the differential drive nano-positioning platform proposed by the present utility model includes a base 1 and a working platform 2 located above the base 1. The base 1 is provided with a "U" - shaped structure. The working platform 2 is arranged parallel to the upper part of the base 1. The working platform 2 is used to connect devices to achieve precise positioning of the devices.

[0033] Furthermore, the above - mentioned positioning platform further includes at least one set of guide rail assemblies 3 arranged between the base 1 and the working platform 2. The guide rail assemblies 3 are installed on the top of the base 1. The guide rail assemblies 3 are fixedly connected to the bottom of the working platform 2. An installation groove 11 is formed on the top of the base 1. The guide rail assemblies 3 are installed in the installation groove 11, making the overall structure of the positioning platform more compact through the installation groove 11. The movement of the working platform 2 is made stable by the arrangement of the guide rail assemblies 3. The guide rail assemblies 3 adopt ball guide rails or crossed roller guide rails, which have higher precision compared to ordinary ball guide rails.

[0034] Specifically, please refer to Figure 1 and Figure 2The aforementioned positioning platform also includes a differential drive mechanism 4 mounted on the base 1. The differential drive mechanism 4 includes a servo motor 44 movably mounted, which slides with the base 1 or the working platform 2. A coaxial rod is fixedly connected to the output end of the servo motor 44. The coaxial rod consists of two lead screws with the same direction of rotation but different leads. The base 1 and the working platform 2 are respectively threaded with one lead screw. When the coaxial rod rotates, the displacement of the working platform 2 changes according to the difference in the leads of the two lead screws, thereby achieving more precise displacement. A groove 12 is provided in the base 1. The differential drive mechanism 4 also includes a mounting block 43 fixedly connected to the servo motor 44. When the servo motor 44 moves, it drives the mounting block 43 to move synchronously. A slide rail 42 is fixedly connected to one side of the mounting block 43. A slider 41 is slidably connected in the slide rail 42. The slider 41 is fixedly connected to the groove 12 or the bottom of the working platform 2. When the position of the slider 41 is fixed, the mounting block 43 moves smoothly under the limiting action of the slider 41 and the slide rail 42. The coaxial rod consists of a first lead screw 45 and a second lead screw 46 connected coaxially. After starting, the servo motor 44 drives the first lead screw 45 and the second lead screw 46 to rotate synchronously. The first lead screw 45 and the second lead screw 46 are arranged parallel to the guide rail assembly 3, thus limiting the movement of the work platform 2 via the guide rail assembly 3. A second threaded sleeve 47 is threaded onto the second lead screw 46, and a fixing plate 48 is fixedly connected to the outer ring of the second threaded sleeve 47. The fixing plate 48 is fixedly connected to the base 1. Because the positions of the second threaded sleeve 47 and the fixing plate 48 are fixed, the second lead screw 46 moves along its own length direction when rotating, simultaneously driving the first lead screw 45 and the servo motor 44 to move synchronously. A first threaded sleeve 49 is threaded onto the first lead screw 45, and when the first lead screw 45 rotates, it drives the first threaded sleeve 49 to move along the length direction of the first lead screw 45. The outer ring of the first threaded sleeve 49 is fixedly connected to the connecting plate 410, which is fixedly connected to the bottom of the working platform 2. When the first threaded sleeve 49 moves, it drives the working platform 2 to move synchronously through the connecting plate 410.

[0035] It is worth mentioning that, since the first lead screw 45 and the second lead screw 46 have the same direction of rotation and different leads, assuming the lead of the first lead screw 45 is 0.4 mm and the lead of the second lead screw 46 is 0.5 mm, when the servo motor 44 drives the first lead screw 45 and the second lead screw 46 to rotate one revolution, because the second threaded sleeve 47 and the fixed plate 48 are fixed in position, the second lead screw 46 moves 0.5 mm along its own length direction when it rotates one revolution, thereby driving the first lead screw 45 and the servo motor 44 to move 0.5 mm. Since the first lead screw 45 and the second lead screw 46 have the same direction of rotation, when the first lead screw 45 rotates one revolution, it drives the work platform 2 to move 0.4 mm in the opposite direction through the first threaded sleeve 49 and the connecting plate 410. Therefore, when the servo motor 44 drives the first lead screw 45 and the second lead screw 46 to rotate one revolution, the work platform 2 only moves 0.1 mm, achieving precise adjustment of the position of the work platform 2.

[0036] Finally, the aforementioned positioning platform also includes a displacement measuring unit 5 disposed on the side of the base 1. The displacement measuring unit 5 includes a grating ruler and a reading head. The grating ruler is mounted on the side of the base 1, and the reading head is fixedly connected to the working platform 2. A synchronization plate 51 is fixedly connected to the reading head, and the reading head is either fixedly connected to the side of the working platform 2 via the synchronization plate 51 or directly omitting the synchronization plate 51 and being fixedly connected to the working platform 2. The displacement measuring unit 5 is used to accurately measure the moving distance of the working platform 2, facilitating the adjustment of the rotation number of the servo motor 44 in conjunction with the control module, thereby achieving precise adjustment of the position of the working platform 2.

[0037] In this embodiment, the servo motor 44 is activated, and its output drives the first lead screw 45 and the second lead screw 46 to rotate synchronously. Since the second lead screw 46 is threadedly connected to the second threaded sleeve 47 fixed on the base 1, and the second threaded sleeve 47 is relatively fixed to the base 1 via the fixing plate 48, according to the lead screw transmission principle, the second lead screw 46 will move along its own length direction when rotating, and the distance of movement is equal to its lead. Taking a lead of 0.5mm for the second lead screw 46 as an example, it will move 0.5mm in a certain direction when rotating one revolution, simultaneously driving the first lead screw 45 and the servo motor 44, which are fixedly connected to it, to move synchronously by 0.5mm. The servo motor 44, through the cooperation of the mounting block 43, the slide rail 42, and the slider 41, ensures that this movement is smooth and occurs in a straight line.

[0038] Meanwhile, the first lead screw 45 rotates as it moves with the second lead screw 46. Since the first lead screw 45 is threadedly connected to the first threaded sleeve 49, and the first threaded sleeve 49 is fixed to the working platform 2 via the connecting plate 410, the rotation of the first lead screw 45 will cause the first threaded sleeve 49 to move along the length of the first lead screw 45, and the moving distance is equal to the lead of the first lead screw 45. Because the first lead screw 45 and the second lead screw 46 have the same direction of rotation, assuming the lead of the first lead screw 45 is 0.4mm, the first threaded sleeve 49 will cause the working platform 2 to move 0.4mm in the opposite direction to the movement of the second lead screw 46.

[0039] Through the aforementioned differential motion, when the servo motor 44 drives the first lead screw 45 and the second lead screw 46 to rotate one revolution, the 0.5mm movement brought by the second lead screw 46 and the reverse 0.4mm movement brought by the first lead screw 45 are superimposed, ultimately causing the working platform 2 to produce only a 0.1mm displacement, thus achieving the effect of amplifying and adjusting accuracy through lead difference.

[0040] Throughout the adjustment process, the two sets of guide rail assemblies 3 at the bottom of the work platform 2 cooperate with the mounting slots 11 on the base 1 to provide high-precision guidance and support for the work platform 2, ensuring its smooth movement. At the same time, the displacement measurement units 5 on both sides of the base 1 monitor the actual displacement of the work platform 2 in real time through the synchronization plate 51 and feed the data back to the control module. The control module adjusts the number of rotations of the servo motor 44 according to the feedback information to further ensure the positioning accuracy of the work platform 2.

[0041] Example 2

[0042] like Figures 1 to 3 As shown, based on Embodiment 1, the differential drive nanopositioning platform also includes a base 1 and a working platform 2, a guide rail assembly 3 and a differential drive mechanism 4 mounted thereon.

[0043] Specifically, the two sets of bases 1 are orthogonally arranged, with the upper base 1 fixedly connected to the top of the work platform 2, and the two sets of guide rail assemblies 3 are perpendicular to each other. At the same time, in order to make the structure compact, the thickness of the connection between the base 1 and the work platform 2 can be reduced.

[0044] In this embodiment, when adjustment is needed in a certain direction (e.g., the X-axis direction) within the plane of the positioning platform, the servo motor 44 of the lower positioning platform is activated. Through the differential motion of the first lead screw 45 and the second lead screw 46, the lower working platform 2 is driven to generate high-precision displacement along the direction (X-axis) of the guide rail assembly 3. The displacement amount is determined by the difference in lead of the two lead screws. At the same time, the lower guide rail assembly 3 ensures that the working platform 2 moves smoothly in the X-axis direction, and the lower displacement measurement unit 5 monitors the displacement in real time and provides feedback to ensure the positioning accuracy in the X-axis direction.

[0045] The upper base 1 is fixedly connected to the top of the lower work platform 2, and the two sets of guide rail assemblies 3 are perpendicular to each other (i.e., the upper guide rail assembly 3 is along the Z-axis). When adjustment is required in a direction perpendicular to the lower adjustment direction (Z-axis), the upper servo motor 44 is activated, and its internal first lead screw 45 and second lead screw 46 also drive the upper work platform 2 to move along the Z-axis through differential motion. Since the work platform 2 moves synchronously with the lower work platform 2, the actual displacement of the upper work platform 2 is the superposition of the lower work platform 2's X-axis displacement and its own Z-axis displacement.

[0046] The above specific embodiments are merely several optional embodiments of this utility model. Based on the technical solution of this utility model and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A differential drive nano-positioning platform, characterized in that, include: A base (1) and a working platform (2) located above the base (1); At least one set of guide rail assemblies (3) are disposed between the base (1) and the working platform (2); The differential drive mechanism (4) is mounted on the base (1). The differential drive mechanism (4) includes a servo motor (44) that is movably set. The output end of the servo motor (44) is fixedly connected to a coaxial rod. The coaxial rod is composed of two lead screws with the same direction of rotation and different leads. The base (1) and the working platform (2) are respectively threaded with a lead screw. When the coaxial rod rotates, the displacement of the working platform (2) is controlled by the difference in the leads of the two lead screws.

2. The differentially driven nano-positioning platform of claim 1, wherein, The guide rail assembly (3) is installed on the top of the base (1) and is fixedly connected to the bottom of the work platform (2).

3. The differentially driven nano-positioning platform of claim 2, wherein, The base (1) has a mounting groove (11) on its top, and the guide rail assembly (3) is installed in the mounting groove (11).

4. The differential drive nano-positioning platform of claim 3, wherein, The differential drive mechanism (4) further includes a mounting block (43) fixedly connected to the servo motor (44). A slide rail (42) is fixedly connected to one side of the mounting block (43). A slider (41) is slidably connected in the slide rail (42). The slider (41) is fixedly connected to the base (1) or the working platform (2).

5. The differential-driven nanopositioning platform according to claim 4, characterized in that, The coaxial rod is composed of a first lead screw (45) and a second lead screw (46) connected in a straight line on the same axis. The first lead screw (45) and the second lead screw (46) are arranged parallel to the guide rail assembly (3). A second threaded sleeve (47) is threadedly connected to the second lead screw (46), and a fixing plate (48) is fixedly connected to the outer ring of the second threaded sleeve (47).

6. The differentially driven nano-positioning platform of claim 5, wherein, The first lead screw (45) is threadedly connected to a first threaded sleeve (49), and the outer ring of the first threaded sleeve (49) is fixedly connected to a connecting plate (410).

7. The differential-driven nanopositioning platform according to claim 6, characterized in that, The fixing plate (48) and the connecting plate (410) are respectively fixedly connected to the base (1) or the working platform (2).

8. The differential-driven nanopositioning platform according to claim 7, characterized in that, It also includes a displacement measuring unit (5) disposed on the side of the base (1). The displacement measuring unit (5) includes a grating ruler and a reading head. The grating ruler is installed on the side of the base (1), and the reading head is fixedly connected to the working platform (2).

9. The differential-driven nanopositioning platform according to claim 8, characterized in that, It also includes a set of bases (1) and a working platform (2), a guide rail assembly (3) and a differential drive mechanism (4) mounted thereon. The two sets of bases (1) are orthogonally arranged, and the upper set of bases (1) is fixedly connected to the top of the working platform (2).

10. The differential-driven nanopositioning platform according to claim 1, characterized in that, The servo motor (44) is slidably coupled with the base (1) or the working platform (2).

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