A linear motor high-precision displacement platform

Abstract

The present invention discloses a high-precision linear motor displacement platform, belonging to the field of precision engineering technology. The high-precision linear motor displacement platform comprises a lower table, the upper side of which is connected to an upper table via a movable module area. In the present invention, a first X-axis movable module, a second X-axis movable module, and a Y-axis movable module are arranged in the movable module area between the lower and upper tables, with three sets of linear motor assemblies. These assemblies are guided by a cross-roller guide and a disc bearing, driven by an integrated driven module, and equipped with three high-resolution grating encoders. This achieves a repeatability accuracy within ±0.3μm. Furthermore, the use of an external laser interferometer can significantly improve the positioning accuracy of the displacement platform, making it suitable for scientific research, industrial manufacturing, and the manufacture and calibration of precision instruments.

Description

Technical Field

[0001] The present invention relates to the field of precision engineering technology, and in particular to a high-precision displacement platform for a linear motor. Background Art

[0002] A high-precision displacement stage is a device used to precisely control position and attitude. It is designed and manufactured to achieve very high position repeatability and stability. It usually consists of a platform and at least three electric or hydraulically driven degree-of-freedom controllers that can move the platform in different directions and maintain it at a given position and orientation.

[0003] High-precision displacement platforms typically have micron-level position repeatability, extremely high stiffness and damping, and attitude stability as low as a few arc seconds. They are often used in scientific research, industrial manufacturing, and the manufacture and calibration of precision instruments. In these applications, extremely high position and attitude accuracy is required. For example, in optical systems, high-precision displacement platforms are required to achieve laser alignment and optical path adjustment.

[0004] The existing displacement platform structure is usually composed of an upper table, a lower bottom and four sets of sliders in the middle. Each set of sliders is guided by a cross roller guide and a cross roller bearing. The three sets of belt drives are driven by a small lead ball screw. The standard stepper motor can also be replaced with a servo motor. This method is relatively good for ordinary ±1μm repeatability. However, it cannot meet the repeatability requirement of 1μm in special industries. Therefore, technicians in this field have proposed a linear motor high-precision displacement platform. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that when the displacement platform in the prior art has a repeatability requirement of 1 μm in special industries, the operation displacement accuracy cannot effectively meet the equipment requirements, and a linear motor high-precision displacement platform is proposed.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A linear motor high-precision displacement platform includes: a lower table, the upper side of which is connected to an upper table via a mobile module area, and a first X-direction mobile module, a second X-direction mobile module, a Y-direction mobile module, and an integrated driven module are sequentially arranged along the same horizontal plane on the mobile module area. The first X-direction mobile module, the second X-direction mobile module, and the Y-direction mobile module are used to drive the mobile module area to perform precise horizontal movement.

[0008] During use, the corresponding linear motor assemblies and grating encoders on the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module are first electrically connected to the external control system, and the corresponding control program is set. The linear motor assemblies on the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module are respectively started using the control system. The cross rollers on the guide device 2 slide with the guide rails 1 and 2, combined with the rotational cooperation of the disc bearing 1 as a guide, and the calculation formula in the control system are used to achieve precise horizontal movement of the upper table. Among them, the disc bearing 2 and the guide device 1 on the integrated driven module cooperate to play a subordinate role in the movement of the upper table. In combination with the three sets of high-resolution grating encoders on the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module, high-precision, high-speed, and high-accuracy linear motion can be achieved. The above structure can achieve a repeatability of ±0.3μm. Finally, the operator can also use an external laser interferometer to significantly improve the positioning accuracy of the displacement platform.

[0009] Furthermore, the lower table is sequentially provided with installation area 1, installation area 2, installation area 3, and installation area 4, and the installation area 1, installation area 2, installation area 3, and installation area 4 correspond to the installation positions of the first X-axis moving module, the second X-axis moving module, the Y-axis moving module, and the integrated driven module, respectively.

[0010] Furthermore, the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module are all provided with a base one, and a linear motor assembly and a grating encoder are provided on the upper part of the base one, and the grating encoder is located on the side of the linear motor assembly. An intermediate U-shaped block is slidably connected to the upper side of the intermediate U-shaped block, and a top cover is slidably connected to the upper side of the intermediate U-shaped block. A disk bearing one is fixedly connected to the upper side of the top cover by bolts, and the disk bearing one is fixedly connected to the lower side of the upper table by bolts. The connection parts between the intermediate U-shaped block and the base one, and the connection parts between the top cover and the intermediate U-shaped block are all slidably connected by providing a guide device two, and the sliding directions of the top cover and the intermediate U-shaped block are perpendicular.

[0011] Furthermore, the guide device 2 is provided with a guide rail 1, a cross roller, and a guide rail 2. The cross roller is located between the guide rail 1 and the guide rail 2 to achieve relative sliding of the connection parts between the blocks.

[0012] By arranging two sets of guide devices 2 at the connection part between the middle U-shaped block and the base 1, and at the connection part between the top cover and the middle U-shaped block respectively, the cross rollers on the guide device 2 can be utilized to slide with the guide rails 1 and 2, which has the characteristics of long service life, strong load capacity, low noise, low friction, and easy maintenance, making the equipment more stable and reliable during operation.

[0013] Furthermore, a reserved groove is provided on the inner side of the middle U-shaped block, which is used to reserve a certain space for the installation and fixation of the grating encoder.

[0014] Furthermore, the integrated driven module is provided with a base two, an intermediate block is slidably connected to the upper side of the base two, an upper U-shaped block is slidably connected to the upper side of the intermediate block, a disc bearing two is fixedly connected to the upper side of the upper table by bolts, the connecting part between the intermediate block and the base two, and the connecting part between the upper U-shaped block and the intermediate block are both slidably connected by setting a guide device one, and the sliding direction of the intermediate block is perpendicular to that of the upper U-shaped block.

[0015] When the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module are driven by the disc bearing 1 to move the upper table in the X direction or the Y direction under the action of the linear motor assembly, the disc bearing 2 connected to the integrated driven module will drive the upper U-shaped block to move horizontally in the Y direction under the action of the guide device 1, and drive the middle block to move horizontally in the X direction under the action of the guide device 1.

[0016] Furthermore, the guide device is provided with a slider and a slide groove for realizing relative sliding of the connection parts between the blocks.

[0017] Furthermore, the outer peripheries of the X-axis first moving module and the integrated driven module are fixedly connected to the upper surface of the lower table through a fixing block.

[0018] Furthermore, the distance moved by the mobile module area along each axis can be calculated according to the following formula:

[0019] △X1=Rcos(θ+X1+△θ)-Rcos(X1+△θ)

[0020] △Y=Rsin(θ+Y+△θ)-Rsin(Y+△θ)

[0021] △X2=Rcos(θ+X2+△θ)-Rcos(X2+△θ)

[0022] Among them, △θ is the last rotation angle, which is 0 at the origin.

[0023] Compared with the prior art, the present invention provides a linear motor high-precision displacement platform with the following beneficial effects:

[0024] 1. By arranging the first X-axis moving module, the second X-axis moving module, and the Y-axis moving module between the lower and upper tables, and matching them with three sets of linear motor assemblies, guided by a cross roller guide and a disc bearing, and driven by an integrated follower module, and equipped with three high-resolution grating encoders, a repeatability accuracy of within ±0.3μm is achieved. In addition, the use of an external laser interferometer can significantly improve the positioning accuracy of the displacement platform, making it suitable for scientific research, industrial manufacturing, and the manufacture and calibration of precision instruments.

[0025] 2. Through the mutual cooperation of guide rail 1, cross roller and guide rail 2 on guide device 2, the equipment has the characteristics of long life, strong load capacity, low noise, low friction and easy maintenance, which can make the equipment more stable and reliable during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a structural schematic diagram of a linear motor high-precision displacement platform proposed by the present invention;

[0027] Figure 2 This is an exploded view of a linear motor high-precision displacement platform proposed by the present invention;

[0028] Figure 3 This is a schematic structural diagram of the mobile module area of ​​a linear motor high-precision displacement platform proposed by the present invention;

[0029] Figure 4 This is an exploded view of the first X-axis moving module of a linear motor high-precision displacement platform proposed by the present invention;

[0030] Figure 5 This is a schematic diagram of the reserved slot structure of a linear motor high-precision displacement platform proposed by the present invention;

[0031] Figure 6 This is an exploded view of an integrated driven module of a linear motor high-precision displacement platform proposed by the present invention;

[0032] Figure 7 This is a schematic diagram of the lower table structure of a linear motor high-precision displacement platform proposed by the present invention;

[0033] Figure 8 This is a schematic diagram of the top view of the linear motor high-precision displacement platform proposed in the present invention.

[0034] In the figure: 1. Lower table; 101. Installation area 1; 102. Installation in area 2; 103. Installation area 3; 104. Installation area 4; 2. Upper table; 3. First X-axis moving module; 31. Base 1; 32. Middle U-shaped block; 33. Top cover; 34. Disc bearing 1; 4. Second X-axis moving module; 5. Y-axis moving module; 6. Integrated driven module; 61. Base 2; 62. Middle block; 63. Upper U-shaped block; 64. Disc bearing 2; 65. Guide device 1; 651. Slider; 652. Slide; 7. Moving module area; 8. Guide device 2; 81. Guide rail 1; 82. Cross roller; 83. Guide rail 2; 9. Linear motor assembly; 10. Grating encoder; 11. Fixed block; 12. Reserved slot. Implementation Method

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0036] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are 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 direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention. Example

[0037] Reference Figure 1-8 A linear motor high-precision displacement platform includes: a lower table 1, the upper side of the lower table 1 is connected to the upper table 2 through a mobile module area 7, and the mobile module area 7 is sequentially provided with an X-direction first mobile module 3, an X-direction second mobile module 4, a Y-direction mobile module 5, and an integrated driven module 6 along the same horizontal plane. The X-direction first mobile module 3, the X-direction second mobile module 4, and the Y-direction mobile module 5 are used to drive the mobile module area 7 to perform precise horizontal movement.

[0038] Working principle: When the present invention is used, it is preferred to electrically connect the corresponding linear motor components 9 and grating encoders 10 on the first X-axis moving module 3, the second X-axis moving module 4, and the Y-axis moving module 5 to the external control system, and set the corresponding control program. The control system is used to start the linear motor components 9 on the first X-axis moving module 3, the second X-axis moving module 4, and the Y-axis moving module 5 respectively, and the cross rollers 82 on the guide device 2 8 are slidably matched with the guide rail 1 81 and the guide rail 2 83, combined with the rotational match of the disc bearing 1 34 as a guide, and the calculation formula in the control system is used to achieve the precise movement of the upper table 2 in the horizontal position. Among them, the disc bearing 2 64 and the guide device 1 65 on the integrated driven module 6 cooperate to play the role of slave cooperation in the movement of the upper table 2, and cooperate with the first X-axis moving module 3 and the second X-axis moving module 4. The three groups of high-resolution grating encoders 10 on module 4 and the Y-moving module 5 generate a magnetic field in the thruster when the linear motor assembly 9 is subjected to current. The grating encoders 10 measure the position and speed of the thruster, and the digital signals they output are used to control the movement of the linear motor assembly 9. By measuring the linear position output, the thrust position of the linear motor assembly 9 can be accurately measured, and on this basis, the position and speed feedback control of the linear motor assembly 9 can be performed. In this way, the combination of the grating encoder 10 and the linear motor assembly 9 can achieve high-precision, high-speed, and high-precision linear motion. The above structure can achieve a repeatability of ±0.3μm. Finally, the operator can also use an external device, a laser interferometer, to use the coherence and interference phenomenon of the laser to measure the displacement accuracy of the object, thereby greatly improving the positioning accuracy of the displacement platform.

[0039] The lower table 1 is provided with an installation area 101, an installation area 102, an installation area 3 103, and an installation area 4 104 in sequence. The installation area 101, the installation area 102, the installation area 3 103, and the installation area 4 104 correspond to the installation positions of the first X-axis moving module 3, the second X-axis moving module 4, the Y-axis moving module 5, and the integrated driven module 6, respectively.

[0040] The first X-axis moving module 3, the second X-axis moving module 4, and the Y-axis moving module 5 are all provided with a base 31. A linear motor assembly 9 and a grating encoder 10 are provided on the upper part of the base 31. The grating encoder 10 is located on the side of the linear motor assembly 9. The upper side of the base 31 is slidably connected to an intermediate U-shaped block 32. The upper side of the intermediate U-shaped block 32 is slidably connected to a top cover 33. The upper side of the top cover 33 is fixedly connected to a disk bearing 34 by bolts. The disk bearing 34 is fixedly connected to the lower side of the upper table 2 by bolts. The connection part between the intermediate U-shaped block 32 and the base 31, and the connection part between the top cover 33 and the intermediate U-shaped block 32 are both slidably connected by setting a guide device 2 8, and the sliding directions of the top cover 33 and the intermediate U-shaped block 32 are perpendicular.

[0041] The guide device 2 8 is provided with a guide rail 1 81, a cross roller 82, and a guide rail 2 83. The cross roller 82 is located between the guide rail 1 81 and the guide rail 2 83 to achieve relative sliding of the connection parts between the blocks.

[0042] like Figure 4 、 Figure 5 As shown, by respectively providing two sets of guide devices 2 8 at the connection portion between the middle U-shaped block 32 and the base 1 31 and at the connection portion between the top cover 33 and the middle U-shaped block 32, the sliding cooperation between the cross rollers 82 on the guide device 2 8 and the guide rails 1 81 and 2 83 can be utilized, which has the characteristics of long life, strong load capacity, low noise, low friction, and easy maintenance, making the equipment more stable and reliable during operation.

[0043] A reserved groove 12 is provided on the inner side of the middle U-shaped block 32 to reserve a certain space for the installation and fixation of the grating encoder 10 .

[0044] The integrated driven module 6 is provided with a second base 61, an intermediate block 62 is slidably connected to the upper side of the second base 61, an upper U-shaped block 63 is slidably connected to the upper side of the intermediate block 62, a second disk bearing 64 is fixedly connected to the upper side of the upper table 2 by bolts, and the second disk bearing 64 is fixedly connected to the lower side of the upper table 2 by bolts. The connection between the intermediate block 62 and the second base 61 and the connection between the upper U-shaped block 63 and the intermediate block 62 are both slidably connected by providing a guide device 65, and the sliding directions of the intermediate block 62 and the upper U-shaped block 63 are perpendicular;

[0045] like Figure 6 As shown, when the first X-axis moving module 3, the second X-axis moving module 4, and the Y-axis moving module 5 are driven by the disc bearing 1 34 to move in the X direction or the Y direction under the action of the linear motor assembly 9, the upper U-shaped block 63 will be driven by the disc bearing 2 64 connected to the integrated driven module 6 to move horizontally in the Y direction under the action of the guide device 1 65, and the middle block 62 will be driven to move horizontally in the X direction under the action of the guide device 1 65.

[0046] The guide device 1 65 is provided with a slider 651 and a slide groove 652 for realizing relative sliding of the connection parts between the blocks.

[0047] The outer peripheries of the X-axis first moving module 3 and the integrated driven module 6 are fixedly connected to the upper surface of the lower table 1 through the fixing block 11 .

[0048] The distance moved by the mobile module area 7 along each axis can be calculated according to the following formula:

[0049] △X1=Rcos(θ+X1+△θ)-Rcos(X1+△θ)

[0050] △Y=Rsin(θ+Y+△θ)-Rsin(Y+△θ)

[0051] △X2=Rcos(θ+X2+△θ)-Rcos(X2+△θ)

[0052] Among them, △θ is the last rotation angle, which is 0 at the origin;

[0053] like Figure 8 As shown, in the original state:

[0054] The node coordinates of X1 are (107.5, -107.5),

[0055] The node coordinates of X2 are (107.5, 107.5),

[0056] The node coordinates of Y are (-107.5, 107.5),

[0057] For example: R=152.03, X1=225°, Y=135°, X2=45°. The distance each axis moves when rotating 1° (θ=1°) is as follows:

[0058] △X1=152.03cos (1° +225° +0°)-152.03cos (225° +0°)

[0059] △X1=-105.61+107.50

[0060] △X1=1.89

[0061] △Y=152.03sin(1° +135° +0°)-152.03sin(135° +0°)

[0062] △Y=105.61-107.50

[0063] △Y==1.89

[0064] △X2=152.03cos (1° +45° +0° )-152. 03cos (45° +0°)

[0065] △X2=105.61=107.50

[0066] △X2=-1.89.

[0067] In the present invention, by arranging the first X-direction moving module 3, the second X-direction moving module 4, and the Y-direction moving module 5 between the lower table 1 and the upper table 2, and matching three sets of linear motor assemblies 9, with a cross roller guide and a disc bearing as the guide, a set of integrated driven modules 6 as the slave, and matching three high-resolution grating encoders 10, a repeatability accuracy within ±0.3μm is achieved, and the use of an external device laser interferometer can greatly improve the positioning accuracy of the displacement platform, making it suitable for scientific research, industrial manufacturing and the manufacture and calibration of precision instruments; through the mutual cooperation of the guide rail 1 81, the cross roller 82, and the guide rail 2 83 on the guide device 2 8, the equipment has the characteristics of long life, strong load capacity, low noise, low friction, easy maintenance, etc., which can make the equipment more stable and reliable during operation.

[0068] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A linear motor high-precision displacement platform, characterized in that: include: A lower table (1), the upper side of the lower table (1) is connected to the upper table (2) via a mobile module area (7), the mobile module area (7) is provided with an X-direction first mobile module (3), an X-direction second mobile module (4), a Y-direction mobile module (5), and an integrated driven module (6) in sequence along the same horizontal plane, the X-direction first mobile module (3), the X-direction second mobile module (4), and the Y-direction mobile module (5) being used to drive the mobile module area (7) to perform precise horizontal movement; The first X-axis moving module (3), the second X-axis moving module (4), and the Y-axis moving module (5) are all provided with a base (31); a linear motor assembly (9) and a grating encoder (10) are provided on the upper part of the base (31); the grating encoder (10) is located on the side of the linear motor assembly (9); an intermediate U-shaped block (32) is slidably connected to the upper side of the intermediate U-shaped block (32); a top cover (33) is slidably connected to the upper side of the top cover (33); a disk bearing (34) is fixedly connected to the lower side of the upper table (2) by bolts at the upper side of the top cover (33); the connecting portion between the intermediate U-shaped block (32) and the base (31) and the connecting portion between the top cover (33) and the intermediate U-shaped block (32) are all slidably connected by providing a guide device (8); and the sliding directions of the top cover (33) and the intermediate U-shaped block (32) are perpendicular to each other; The second guide device (8) is provided with a guide rail (81), a cross roller (82), and a guide rail (83). The cross roller (82) is located between the guide rail (81) and the guide rail (83) to achieve relative sliding of the connection parts between the blocks. A reserved groove (12) is provided on the inner side of the middle U-shaped block (32) for reserving a certain space for the installation and fixation of the grating encoder (10); The linear motor components (9) and grating encoders (10) corresponding to the first X-axis moving module (3), the second X-axis moving module (4), and the Y-axis moving module (5) are electrically connected to an external control system, and corresponding control programs are set. The linear motor components (9) on the first X-axis moving module (3), the second X-axis moving module (4), and the Y-axis moving module (5) are respectively started by the control system. The cross rollers (82) on the guide device 2 (8) are slidably matched with the guide rail 1 (81) and the guide rail 2 (83), and the rotational match of the disc bearing 1 (34) is used as a guide to achieve precise movement of the upper table (2) in a horizontal position. Among them, the disc bearing 2 (64) and the guide device 1 (65) on the integrated driven module (6) cooperate to play the role of subordinate cooperation in the movement of the upper table (2), and cooperate with the first X-axis moving module (3), the second X-axis moving module (4), and the Y-axis moving module (5). The three groups of high-resolution grating encoders (10) on the block (4) and the Y-movement module (5) generate a magnetic field in the thruster when the linear motor assembly (9) is subjected to current. The grating encoders (10) measure the position and speed of the thruster. The digital signals output by them are used to control the movement of the linear motor assembly (9). By measuring the linear position output, the thrust position of the linear motor assembly (9) can be accurately measured, and on this basis, the position and speed feedback control of the linear motor assembly (9) can be performed. In this way, the grating encoders (10) and the linear motor assembly (9) can be used in combination to achieve high-precision, high-speed, and high-precision linear movement, and can achieve ±0.3μm repeatability. Finally, the operator can also use the external device laser interferometer to use the coherence and interference phenomenon of the laser to measure the displacement accuracy of the object, thereby greatly improving the positioning accuracy of the displacement platform.

2. A linear motor high-precision displacement platform according to claim 1, characterized in that: The lower table (1) is provided with an installation area 1 (101), an installation area 2 (102), an installation area 3 (103), and an installation area 4 (104) in sequence. The installation area 1 (101), the installation area 2 (102), the installation area 3 (103), and the installation area 4 (104) respectively correspond to the installation positions of the first X-direction moving module (3), the second X-direction moving module (4), the Y-direction moving module (5), and the integrated driven module (6).

3. The linear motor high-precision displacement platform according to claim 1, characterized in that: The integrated driven module (6) is provided with a second base (61), an intermediate block (62) is slidably connected to the upper side of the second base (61), an upper U-shaped block (63) is slidably connected to the upper side of the intermediate block (62), a second disk bearing (64) is fixedly connected to the upper side of the upper table (2) by bolts, and the second disk bearing (64) is fixedly connected to the lower side of the upper table (2) by bolts. The connection part between the intermediate block (62) and the second base (61) and the connection part between the upper U-shaped block (63) and the intermediate block (62) are both slidably connected by providing a guide device (65), and the sliding directions of the intermediate block (62) and the upper U-shaped block (63) are perpendicular.

4. The linear motor high-precision displacement platform according to claim 3, characterized in that: The guide device 1 (65) is provided with a slider (651) and a slide groove (652) for realizing relative sliding of the connection parts between the blocks.

5. The linear motor high-precision displacement platform according to claim 4, characterized in that: The outer peripheries of the X-direction first moving module (3) and the integrated driven module (6) are fixedly connected to the upper surface of the lower table (1) via a fixing block (11).

6. The linear motor high-precision displacement platform according to claim 5, characterized in that: The distance that the mobile module area (7) moves along each axis can be calculated according to the following formula: △X1=Rcos(θ+X1+△θ)-Rcos(X1+△θ) △Y=Rsin(θ+Y+△θ)-Rsin(Y+△θ) △X2=Rcos(θ+X2+△θ)-Rcos(X2+△θ) where △θ is the angle of the last rotation, which is 0 at the origin.

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