CN102944980A - Microchecker having permanent magnet gravity support structure - Google Patents

Abstract

A micro-motion table with a permanent magnet gravity support structure is mainly used in a photolithography machine workpiece table system. The micro-motion table includes a micro-motion table stator, a micro-motion table mover, and at least three permanent magnet gravity support units, and the at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z-axis of the micro-motion table ; Each permanent magnet gravity support unit contains a fixed part and a supporting part; the fixed part is a hollow cylindrical permanent magnet, and the bottom surface of the hollow cylindrical permanent magnet magnetized in the axial direction is an S pole, and the upper bottom surface is an N pole; the supporting part is composed of Composed of two coaxial ring permanent magnets that are magnetized along the radius and pointing to the center of the circle; the hollow cylindrical permanent magnet of the fixed part is arranged coaxially with the double-layer ring permanent magnet, and is located above the double-layer ring permanent magnet . The supporting structure of the present invention can reduce the stiffness along the axial direction within the stroke range, and at the same time improve the bearing capacity.

Description

A kind of micro-motion table with permanent magnet gravity support structure

technical field

The invention relates to a micro-motion table with a permanent magnet gravity support structure, in particular to an ultra-precision workbench for integrated circuit processing and testing equipment, belonging to the field of ultra-precision processing and measurement.

Background technique

In many industrial equipments, it is necessary to drive the workpiece or the workpiece table for multi-degree-of-freedom movement and precisely position it, such as the workpiece table and mask table in the lithography machine. In order to achieve multi-degree-of-freedom motion and precise positioning, if the drive motor is directly used to provide support, the load on the drive motor will increase, resulting in increased heat generation of the motor. In many ultra-precision workbenches, if the motor heats up too much, it will affect the ambient temperature, cause non-contact measurement errors, and ultimately affect the positioning accuracy. The permanent magnet non-contact gravity compensation structure has the advantages of simple structure, no need for precision machining on the surface of parts, and is suitable for applications in vacuum environments. For the non-contact permanent magnet gravity support structure, it is necessary to have less rigidity and greater bearing capacity along the axial direction between the fixed part and the supporting part.

Sven Antoin Johan Hol proposed a permanent magnet preload gravity support structure in the patent "Lithographic apparatus, magnetic support for use therein, device manufacturing method, and device manufactured thereby" (US 6831285 B2 Dec.2004), but the structure is complicated, And the processing and assembly process is difficult. With the development of lithography machine technology, the silicon wafer table can be lighter, and its load requirements are also reduced. However, with the development and use of the maglev work table, and the large-stroke motion table of the maglev work table contains a large Halbach magnetic steel array , generating a strong magnetic field will have a greater impact on the gravity balance effect of the micro-motion stage mover in the working state.

Contents of the invention

The purpose of the present invention is to provide a micro-motion table with a permanent magnet gravity support structure, so that the stiffness between the mover and the stator along the axial direction is close to zero, and has a large bearing capacity, and at the same time has a simple structure and is easy to process And maintenance.

Technical scheme of the present invention is as follows:

The first technical solution of the present invention is: a micro-motion table with a permanent magnet gravity support structure, the micro-motion table includes a micro-motion table stator and a micro-motion table mover, and it is characterized in that: the micro-motion table also includes at least three A permanent magnet gravity support unit, the at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the described The fixed part is a hollow cylindrical permanent magnet and a magnetic steel mandrel. The hollow cylindrical permanent magnet is bonded on the magnetic steel mandrel. The magnetization direction of the hollow cylindrical permanent magnet is along the axial direction of the cylinder, and the bottom surface is the S pole. The upper bottom surface is an N pole; the supporting part is composed of an inner ring permanent magnet, an outer ring permanent magnet and a magnetic steel frame, and the two ring permanent magnets are coaxially bonded on the magnetic steel frame, The magnetization direction of the two ring permanent magnets is along the radius and points to the center of the circle; the hollow cylindrical permanent magnet of the fixed part is coaxially arranged with the inner ring permanent magnet and the outer ring permanent magnet, and is located at the two Above the ring permanent magnet; the hollow cylindrical permanent magnet of the fixed part of each permanent magnet gravity support unit is connected on the stator of the micro-motion table through the magnetic steel mandrel, and the inner ring permanent magnet of the support part of the permanent magnet gravity support unit and The outer ring permanent magnet is connected to the mover of the micro-motion table through the magnetic steel skeleton.

The second technical solution of the present invention is: a micro-motion table with a permanent magnet gravity support structure, the micro-motion table includes a micro-motion table stator and a micro-motion table mover, and it is characterized in that: the micro-motion table also includes at least three A permanent magnet gravity support unit, the at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the described The fixed part is a hollow cylindrical permanent magnet and a magnetic steel mandrel. The hollow cylindrical permanent magnet is bonded on the magnetic steel mandrel. The magnetization direction of the hollow cylindrical permanent magnet is along the axial direction of the cylinder, and the bottom surface is the S pole. The upper bottom surface is the N pole; the supporting part is composed of an inner ring permanent magnet, an outer ring permanent magnet and a magnetic steel frame 5, and the two ring permanent magnets are coaxially bonded on the magnetic steel frame , the magnetization direction of the two ring permanent magnets is along the radius and points to the center of the circle; the hollow cylindrical permanent magnet of the fixed part is coaxially arranged with the inner ring permanent magnet and the outer ring permanent magnet, and is located at the two Below the ring permanent magnets; the hollow cylindrical permanent magnet of the fixed part of each permanent magnet gravity support unit is connected on the stator of the micro-motion stage through the magnetic steel mandrel 4, and the inner ring permanent magnet of the support part of the permanent magnet gravity support unit The magnet and the permanent magnet of the outer ring are connected to the mover of the micro-motion table through the magnetic steel skeleton.

The third technical solution of the present invention is: a micro-motion table with a permanent magnet gravity support structure, the micro-motion table includes a micro-motion table stator and a micro-motion table mover, and it is characterized in that: the micro-motion table also includes at least three A permanent magnet gravity support unit, the at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the described The fixed part is a hollow cylindrical permanent magnet and a magnetic steel mandrel, the hollow cylindrical permanent magnet is bonded on the magnetic steel mandrel, the magnetization direction of the hollow cylindrical permanent magnet is along the axial direction of the cylinder, and the lower bottom surface is N pole, The upper bottom surface is the S pole; the supporting part is composed of an inner ring permanent magnet, an outer ring permanent magnet and a magnetic steel frame, and the two ring permanent magnets are coaxially bonded on the magnetic steel frame, The magnetization direction of the two ring permanent magnets is along the radius and facing away from the center of the circle; the hollow cylindrical permanent magnet of the fixed part is coaxially arranged with the inner ring permanent magnet and the outer ring permanent magnet, and is located at the two above the ring permanent magnet; the hollow cylindrical permanent magnet of the fixed part of each permanent magnet gravity support unit is connected on the stator of the micro-motion table through the magnetic steel mandrel, and the inner ring permanent magnet of the support part of the permanent magnet gravity support unit The permanent magnet and the outer ring are connected to the mover of the micro-motion table through the magnetic steel skeleton.

A kind of micro-motion platform with permanent magnet gravity support structure according to the present invention has the following advantages and outstanding effects: the fixed part is a hollow cylindrical permanent magnet magnetized in the axial direction, and the inner and outer ring permanent magnets of the supporting part The coaxial arrangement makes the stiffness between the fixed part and the supporting part along the axis close to zero under the condition that the interaction force between the fixed part and the supporting part in the radial direction and the tangential direction is small. In addition, the present invention has the characteristics of simple structure and convenient processing. This support structure is mainly used in the maglev worktable system of the lithography machine. It raises the hollow cylindrical permanent magnet that is axially magnetized in the fixed part, and also reduces the gravity of the halbach permanent magnet array strong magnetic field of the maglev worktable on the mover part of the micro-motion table. The impact of the balance effect.

Description of drawings

Fig. 1 is a schematic three-dimensional central cross-sectional view of the first permanent magnet gravity support unit according to the present invention.

Fig. 2 is a structural schematic diagram of a micro-motion table with a permanent magnet gravity support structure according to the present invention.

Fig. 3 is a distribution diagram of magnetic lines of force in the central section of the permanent magnet gravity support unit according to the present invention.

Fig. 4 is a schematic three-dimensional central cross-sectional view of the second type of permanent magnet gravity support unit of the present invention.

Fig. 5 is a schematic three-dimensional central cross-sectional view of the third permanent magnet gravity support unit of the present invention.

In the figure: 1-hollow cylindrical permanent magnet; 2-inner ring permanent magnet; 3-outer ring permanent magnet; 4-magnetic steel mandrel; 5-magnetic steel skeleton; Moving table stator.

Detailed ways

The specific structure, mechanism and working process of the present invention will be further described below in conjunction with the accompanying drawings.

Fig. 2 is a schematic structural diagram of a micro-motion table with a permanent magnet gravity support structure according to the present invention. The micro-motion table includes a micro-motion table stator, a micro-motion table mover and at least three permanent magnet gravity support units. Three permanent magnet gravity support units, which are evenly arranged on the edge of the micro-motion table around the Z-axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the fixed part is a hollow A cylindrical permanent magnet 1 and a magnetic steel mandrel 4, the hollow cylindrical permanent magnet 1 is bonded on the magnetic steel mandrel 4, the magnetization direction of the hollow cylindrical permanent magnet 1 is along the axial direction of the cylinder, the lower bottom surface is the S pole, and the upper bottom surface It is an N pole, as shown in Figure 1; the supporting part is composed of an inner ring permanent magnet 2, an outer ring permanent magnet 3 and a magnetic steel frame 5, and the two ring permanent magnets are coaxially bonded to the magnetic steel frame 5, the magnetization direction of the two ring permanent magnets is along the radius and points to the center of the circle; the hollow cylindrical permanent magnet 1 of the fixed part is coaxially arranged with the inner ring permanent magnet 2 and the outer ring permanent magnet 3, and is located at two Above the ring permanent magnet; the hollow cylindrical permanent magnet 1 of the fixed part of each permanent magnet gravity support unit is connected on the stator of the micro-motion table through the magnetic steel mandrel 4, and the inner ring permanent magnet of the support part of the permanent magnet gravity support unit The magnet 2 and the outer ring permanent magnet 3 are connected to the mover of the micro-motion table through the magnetic steel skeleton 5 .

Since the hollow cylindrical permanent magnet 1 axially magnetized in the fixed part attracts the magnetic poles of the two circular permanent magnets in the supporting part, it is always opposite to the gravity direction of the supporting part, and the two phases cancel, thereby stabilizing the supporting part in the A certain position in the space; the vertical distance between the hollow cylindrical permanent magnet of the fixed part and the supporting part is subdivided, and the vertical supporting force is calculated according to the size of the load, and the central horizontal section of the hollow cylindrical permanent magnet 1 in the height direction is set It coincides with the central horizontal section in the height direction of the two ring permanent magnets, and the intersection of the two sections and the Z axis is used as the origin of the reference coordinate system, which is positive along the positive direction of the Z axis and negative on the contrary, so that the hollow cylindrical permanent magnet 1 Translate in the positive direction of the Z axis to obtain a curve about the vertical support force of the hollow cylindrical permanent magnet 1 along the Z axis. According to different size parameters of the hollow cylindrical permanent magnet in the fixed part, a wider range of support force can be obtained. In addition, in the positive and negative directions of the zero point of the vertical distance between the hollow cylindrical permanent magnet in the fixed part and the inner and outer hollow permanent magnets in the supporting part, two points with the same absolute value can be found, which shows that the hollow cylindrical permanent magnet in the fixed part is higher than When the inner and outer hollow permanent magnets of the support part or the hollow cylindrical permanent magnets of the fixed part are lower than the inner and outer hollow permanent magnets of the support part, the support force of the same size can be obtained, and the support force is selected as a certain point, which provides a theory for the present invention in accordance with.

Fig. 4 is a schematic three-dimensional central cross-sectional view of the second permanent magnet gravity support unit of the present invention. According to the curve about the vertical support force of the hollow cylindrical permanent magnet 1 along the Z-axis direction, the absolute For two points with the same value, select another point that is symmetrical to a point selected by the first type of permanent magnet gravity support unit. Compared with the first type of permanent magnet gravity support unit shown in Figure 1, the magnetization direction of the hollow cylindrical permanent magnet 1 of the fixed part of the second type of permanent magnet gravity support unit is along the cylinder axis, the lower bottom surface is the S pole, and the upper bottom surface It is an N pole; the supporting part is composed of two coaxial inner ring permanent magnets 2 magnetized along the radius and pointing to the center of the circle and an outer ring permanent magnet 3 magnetized along the radius and pointing to the center of the circle. The hollow cylindrical permanent magnet of the fixed part The magnet 1 is coaxially arranged with the inner ring permanent magnet 2 and the outer ring permanent magnet 3, and is located below the double-layer ring permanent magnet. Since the hollow cylindrical permanent magnet 1 axially magnetized in the fixed part repels the magnetic poles of the double-layer hollow magnetic ring of the supporting part, it is always opposite to the gravity direction of the supporting part, and the two phases cancel, thereby stabilizing the supporting part in space somewhere in the .

Fig. 5 is a schematic three-dimensional central cross-sectional view of the third permanent magnet gravity support unit of the present invention. Compared with the permanent magnet gravity support structure shown in Figure 1, the magnetization direction of the hollow cylindrical permanent magnet 1 in the fixed part is along the cylinder axis, the lower bottom surface is the N pole, and the upper bottom surface is the S pole; the supporting part consists of two coaxial, The inner ring permanent magnet 2 magnetized along the radius and away from the center of the circle and the outer ring permanent magnet 3 magnetized along the radius and away from the center of the circle, the hollow cylindrical permanent magnet 1 and the inner ring permanent magnet 2 of the fixed part Arranged coaxially with the outer ring permanent magnet 3, and located above the double-layer ring permanent magnet, that is, the magnetization directions of all permanent magnets are all rotated by 180 degrees.

Claims (3)

1. A micro-motion stage with a permanent magnet gravity support structure, the micro-motion stage includes a micro-motion stage stator and a micro-motion stage mover, it is characterized in that: the micro-motion stage also includes at least three permanent magnet gravity support units, so The at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z-axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the fixed part is composed of a hollow cylindrical permanent magnet (1) and a magnetic steel mandrel (4), the hollow cylindrical permanent magnet (1) is bonded on the magnetic steel mandrel (4), and the magnetization direction of the hollow cylindrical permanent magnet (1) is along the cylindrical axis direction, the lower bottom surface is the S pole, and the upper bottom surface is the N pole; the supporting part is composed of an inner ring permanent magnet (2), an outer ring permanent magnet (3) and a magnetic steel skeleton (5). The two ring permanent magnets are coaxially bonded on the magnetic steel skeleton (5), and the magnetization direction of the two ring permanent magnets is along the radius and points to the center of the circle; the hollow cylindrical permanent magnet (1) of the fixed part Arranged coaxially with the inner ring permanent magnet (2) and the outer ring permanent magnet (3), and located above the two ring permanent magnets; the hollow cylindrical permanent magnet of the fixed part of each permanent magnet gravity support unit (1) Connected to the stator of the micro-motion table through the magnetic steel mandrel (4), the inner ring permanent magnet (2) and the outer ring permanent magnet (3) of the support part of the permanent magnet gravity support unit pass through the magnetic steel skeleton (5) Connected to the mover of the micro-motion table. 2. A micro-motion table with a permanent magnet gravity support structure, the micro-motion table includes a micro-motion table stator and a micro-motion table mover, it is characterized in that: the micro-motion table also includes at least three permanent magnet gravity support units, the The at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the fixed part is a hollow cylindrical permanent magnet (1) and a magnetic steel mandrel (4), the hollow cylindrical permanent magnet (1) is bonded on the magnetic steel mandrel (4), and the magnetization direction of the hollow cylindrical permanent magnet (1) is along the axial direction of the cylinder , the lower bottom surface is the S pole, and the upper bottom surface is the N pole; the supporting part is composed of an inner ring permanent magnet (2), an outer ring permanent magnet (3) and a magnetic steel skeleton (5). Two ring permanent magnets are coaxially bonded on the magnetic steel skeleton (5), and the magnetization direction of the two ring permanent magnets is along the radius and points to the center of the circle; the hollow cylindrical permanent magnet (1) of the fixed part is connected with the The inner ring permanent magnet (2) and the outer ring permanent magnet (3) are coaxially arranged and located below the two ring permanent magnets; the hollow cylindrical permanent magnet ( 1) Connected to the stator of the micro-motion table through the magnetic steel mandrel (4), the inner ring permanent magnet (2) and the outer ring permanent magnet (3) of the support part of the permanent magnet gravity support unit pass through the magnetic steel skeleton ( 5) Connected to the mover of the micro-motion table. 3. A micro-motion table with a permanent magnet gravity support structure, the micro-motion table includes a micro-motion table stator and a micro-motion table mover, it is characterized in that: the micro-motion table also includes at least three permanent magnet gravity support units, the The at least three permanent magnet gravity support units are evenly distributed on the edge of the micro-motion table around the Z axis of the micro-motion table; each permanent magnet gravity support unit contains a fixed part and a support part, and the fixed part is a hollow cylindrical permanent magnet (1) and a magnetic steel mandrel (4), the hollow cylindrical permanent magnet (1) is bonded on the magnetic steel mandrel (4), and the magnetization direction of the hollow cylindrical permanent magnet (1) is along the axial direction of the cylinder , the lower bottom surface is the N pole, and the upper bottom surface is the S pole; the supporting part is composed of an inner ring permanent magnet (2), an outer ring permanent magnet (3) and a magnetic steel skeleton (5). Two ring permanent magnets are coaxially bonded on the magnetic steel skeleton (5), and the magnetization direction of the two ring permanent magnets is along the radius and facing away from the center of the circle; the hollow cylindrical permanent magnet (1) of the fixed part Arranged coaxially with the inner ring permanent magnet (2) and the outer ring permanent magnet (3), and located above the two ring permanent magnets; the hollow cylindrical permanent magnet of the fixed part of each permanent magnet gravity support unit (1) Connected to the stator of the micro-motion table through the magnetic steel mandrel (4), the inner ring permanent magnet (2) and the outer ring permanent magnet (3) of the support part of the permanent magnet gravity support unit pass through the magnetic steel skeleton (5) Connected to the mover of the micro-motion table.

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