Three-degree-of-freedom magnetic suspension coreless linear motor

Abstract

A three-degree-of-freedom magnetic suspension coreless linear motor disclosed by the present invention comprises a combined guide rail and an end cover arranged above the combined guide rail, the combined guide rail comprises two magnetic steel guide rails, the two magnetic steel guide rails are connected through screws, and each magnetic steel guide rail comprises a plurality of magnetic steel blocks, two rail side frames and a rail bottom frame. The multiple magnetic steel blocks are arranged at equal intervals, the rail side frames are symmetrically arranged on the two sides of the magnetic steel blocks, the rail bottom frame is arranged at the bottoms of the magnetic steel blocks, a coil carrier is arranged between the two magnetic steel guide rails, and a driving coil and a steering coil are arranged in the coil carrier. Carrier connecting pieces are symmetrically arranged on the two sides of the coil carrier, and the coil carrier and the carrier connecting pieces are connected through screws. By the adoption of the structure, the motor is controlled to move through electromagnetic force, the stability, cleanliness and reliability of the motor are greatly improved, and the motor can be applied to occasions with high precision and high cleanliness requirements.

Description

Technical Field

[0001] The invention relates to the technical field of linear motors, and in particular to a three-degree-of-freedom magnetically suspended coreless linear motor. Background Art

[0002] The automatic material handling system (AMHS) is a crucial technological innovation in the wafer fab, playing a key role in improving production efficiency, reducing costs and enhancing manufacturing competitiveness. The AMHS system of the wafer fab is composed of hardware equipment and fully automatic control software. A large number of AMHS devices realize fully automatic intelligent material handling under the control of the AMHS software, realizing unmanned operation of the wafer fab. An efficient AMHS system can greatly reduce the waiting time of work-in-progress, which is crucial to maintaining and improving the core production indicators of the wafer fab, such as output, utilization rate, and yield. Overhead hoist transport (OHT) realizes the rapid and stable movement of wafers in various processing areas, saves floor space in the clean room, and has become the most widely used handling tool in wafer manufacturing plants.

[0003] In the current high-altitude lifting transportation, most wafer manufacturers use mechanical wheel-rail OHT for transportation, mostly using servo motors, stepper motors and screw transmission modes, which have the advantages of mature technology and simple structure. However, in this type of OHT, the transport trolley and the track are often mechanically connected, which causes friction and wear. The iron filings and dust generated will affect the cleanliness of the clean room and thus the quality of the wafers. Some wafer manufacturers use pneumatic suspension, which effectively reduces the friction and wear of the mechanical track, but there are problems such as complex air source, low support stiffness, and easy leakage, which can easily stir up solid particles in the air and pollute the environment. Magnetic suspension technology has the characteristics of no friction and no wear, and can achieve high precision, low loss, long life, low vibration and other performances. Therefore, it can be used as an ideal support method for the new generation of smart transmission.

[0004] For example, the existing authorized invention patent 202411219342.2 discloses a linear motor with a vibration elimination function, in which a mover is slidably installed inside the housing, a placement table is installed on the top of the mover, a placement slot is opened on the top of the placement table, a placement plate is slidably installed at the bottom of the placement slot, and an electromagnet sheet is installed at the top of the fixed slot in the length direction. By adjusting the magnetic field strength of the two electromagnet sheets, the vibration of the two sides of the placement table is eliminated. This scheme adopts traditional mechanical connection, and there is obvious friction during the movement. The existing authorized invention patent 202411278035.1 discloses a guide rod and vertical roller combined transmission type linear motor module, which uses the cooperation of the roller and the guide rod to form a guide transmission for the slide seat, and the wear between the roller and the guide rod is small, thereby improving the load-bearing capacity and guiding accuracy of the linear motor module, further improving the service life of the linear motor module, and the rollers and guide rods can be produced in a standardized manner, while ensuring the accuracy of the linear motor, reducing the production cost. However, this solution can only reduce friction during movement, but cannot completely solve the friction problem, and cannot be applied to occasions with high cleanliness requirements. The existing authorized invention patent 202411533887.0 discloses an air-cooled linear motor, which allows air to blow directly at the motor body, which can quickly and portablely reduce the motor's operating temperature, increase the motor's thrust density, and reduce friction during operation. However, the air-cooling structure is complex and prone to air leakage, and stability and safety are difficult to guarantee. Summary of the invention

[0005] The purpose of the present invention is to provide a three-degree-of-freedom magnetically suspended coreless linear motor, which applies magnetic suspension technology to the linear motor, reduces or even eliminates the friction during the operation of the motor, and meets the requirements of high cleanliness and high stability.

[0006] To achieve the above-mentioned purpose, the present invention provides a three-degree-of-freedom magnetic levitation coreless linear motor, comprising a combined guide rail and an end cover arranged above the combined guide rail, the combined guide rail comprising two magnetic steel guide rails, the two magnetic steel guide rails being connected by screws, the magnetic steel guide rails each comprising a plurality of magnetic steel blocks, two track side frames and a track base frame, the plurality of magnetic steel blocks being arranged at equal distances, the track side frames being symmetrically arranged on both sides of the magnetic steel blocks, the track base frame being arranged at the bottom of the magnetic steel blocks, a coil carrier being arranged between the two magnetic steel guide rails, a driving coil and a steering coil being arranged inside the coil carrier, carrier connectors being symmetrically arranged on both sides of the coil carrier, and the coil carrier and the carrier connectors being connected by screws.

[0007] Preferably, the NS poles of the magnetic steel blocks are arranged in a staggered manner, and the magnetic lines of force are evenly distributed between the magnetic steel blocks on the upper and lower sides, and complete a closed loop inside the magnetic steel blocks.

[0008] Preferably, the width of the magnetic steel block is 30-50 mm, the height is 3-5 mm, and the spacing between two magnetic steel blocks is not less than 1 mm.

[0009] Preferably, the air gap height between the two magnetic steel guide rails is between 0.5 and 1.5 mm, and the gap height between the two magnetic steel guide rails and the coil carrier is between 0.3 and 0.5 mm.

[0010] Preferably, a slide groove is symmetrically arranged on the outer side of the end cover, a slider is arranged on the inner side of the carrier connector, the slide groove is adapted to the size of the slider, and the slide groove is slidably connected to the slider, and external connection threaded holes are arranged above the end cover and on the outer side of the carrier connector.

[0011] Preferably, the driving coil is wound in parallel with two or three wires, the slot fill rate of the driving coil is not less than 60%, and the width of the driving coil is greater than the width of two or more even numbers of the magnetic steel blocks.

[0012] Preferably, the steering coil is wound in double or triple parallel winding, the slot fill rate of the steering coil is not less than 60%, and the width of the steering coil is less than the width of one magnetic steel block.

[0013] Preferably, the material of the coil carrier is one or more of polyimide, polyphenylene sulfide, polyetheretherketone and polysulfone.

[0014] Preferably, the drive coil and the steering coil are bonded and cured in the frame of the coil carrier by epoxy resin.

[0015] Preferably, a Hall sensor and a grating ruler are respectively arranged on the inner sides of the two carrier connecting plates, the Hall sensor is connected to a host computer, and the host computer is electrically connected to the grating ruler.

[0016] Therefore, the present invention adopts the above-mentioned three-degree-of-freedom magnetic suspension coreless linear motor, which has the following beneficial effects: (1) The magnetic force between the permanent magnet and the coil is used to achieve the suspension and drive of the motor rotor, achieving low-friction or frictionless motion during the movement process. Compared with traditional motors that are mechanically connected by rollers or connecting rods, the friction during the movement process is greatly reduced, and the stability and cleanliness of the motor are improved; compared with pneumatic or gas-assisted motors, there is no need to use complex air circuits, reducing the difficulty of support and the risk of air source leakage.

[0017] (2) The present invention controls the movement of the motor through electromagnetic force, which greatly improves the stability, cleanliness and reliability of the motor. It can be used in situations requiring high precision and high cleanliness, and is particularly suitable for wafer transfer.

[0018] (3) The magnetic force between the permanent magnet and the coil is used to realize the suspension and drive of the motor rotor, achieving low friction or frictionless movement during the movement process, improving the stability of the motor during operation, reducing the pollution of the motor during movement, and realizing ultra-clean and very stable transportation of the motor, which can be applied in wafer transportation, improve the cleanliness of the working area during wafer transportation, and ensure the quality of the wafer.

[0019] (4) Compared with traditional motors that are mechanically connected through rollers or connecting rods, the friction during movement is greatly reduced, and the stability and cleanliness of the motor are improved; compared with pneumatic or gas-assisted motors, there is no need to use complex air circuits, which reduces the difficulty of support and the risk of air source leakage.

[0020] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic structural diagram of a three-degree-of-freedom magnetically suspended coreless linear motor according to an embodiment of the present invention; Figure 2 An exploded view of a three-degree-of-freedom magnetically suspended coreless linear motor according to an embodiment of the present invention; Figure 3 It is a schematic diagram of another angle of a three-degree-of-freedom magnetic suspension coreless linear motor of the present invention; Figure 4 It is a two-dimensional principle schematic diagram of a three-degree-of-freedom magnetically suspended coreless linear motor of the present invention; Figure 5 A schematic diagram of the driving force on the driving coil of the present invention; Figure 6 It is a schematic diagram of the steering force applied to the steering coil of the present invention; Reference numerals 1. Combined guide rail; 2. End cover; 3. Magnetic steel guide rail; 31. Magnetic steel block; 32. Track side frame; 33. Track base frame; 4. Coil carrier; 5. Driving coil; 6. Steering coil; 7. Carrier connector; 8. Slide groove; 9. Slider; 10. Hall sensor; 11. Grating ruler. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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 part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various 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 represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0024] Example like Figure 1-Figure 6 As shown, the present invention provides a three-degree-of-freedom magnetic suspension coreless linear motor, including a combined guide rail 1 and an end cover 2 arranged above the combined guide rail 1, the combined guide rail 1 includes two magnetic steel guide rails 3, the two magnetic steel guide rails 3 are connected by screws, and the magnetic steel guide rails 3 each include a plurality of magnetic steel blocks 31, two track side frames 32 and a track bottom frame 33, the plurality of magnetic steel blocks 31 are arranged at equal distances, the track side frames 32 are symmetrically arranged on both sides of the magnetic steel blocks 31, and the track bottom frame 33 is arranged at the bottom of the magnetic steel blocks 31. The NS poles of the magnetic steel blocks 31 are arranged alternately, and the magnetic lines of force are evenly distributed between the magnetic steel blocks 31 on the upper and lower sides, and a closed loop is completed inside the magnetic steel blocks 31. The width of the magnetic steel blocks 31 is 30-50 mm, the height is 3-5 mm, and the spacing between the two magnetic steel blocks 31 is not less than 1 mm. The air gap height between the two magnetic steel guide rails 3 is between 0.5 and 1.5 mm.

[0025] A coil carrier 4 is arranged between the two magnetic steel rails 3, and the gap height between the two magnetic steel rails 3 and the coil carrier 4 is between 0.3 and 0.5 mm. A driving coil 5 and a steering coil 6 are arranged inside the coil carrier 4, and carrier connectors 7 are symmetrically arranged on both sides of the coil carrier 4, and the coil carrier 4 and the carrier connector 7 are connected by screws.

[0026] A slide groove 8 is symmetrically arranged on the outer side of the end cover 2, and a slider 9 is arranged on the inner side of the carrier connector 7. The slide groove 8 is adapted to the size of the slider 9, and the slide groove 8 is slidably connected to the slider 9. The end cover 2 and the carrier connector 7 are connected through the slide groove 8, which prevents the carrier connector from falling and hitting the magnetic steel guide rail 3 in the power-off state, thereby realizing power-off protection.

[0027] External connection threaded holes are provided above the end cover 2 and on the outside of the carrier connector 7 to achieve connection with the outside of the motor.

[0028] The winding method of the driving coil 5 is double-wire or triple-wire winding to improve the slot fill rate. The slot fill rate of the driving coil 5 is not less than 60%. The width of the driving coil 5 can span more than two even-numbered magnetic steel blocks 31. The opposite currents on both sides of the driving coil 5 along the guide rail direction drive the driving coil 5 and the coil carrier 4 to move under the action of the magnetic steel blocks 31 with different polarities.

[0029] The steering coil 6 is wound in double or triple parallel winding to increase the slot fill rate. The slot fill rate of the steering coil 6 is not less than 60%. The width of the steering coil 6 is less than the width of a magnetic steel block 31. Therefore, the steering coil 6 is not subjected to force along the direction of the magnetic steel guide rail 3, and part of it in the direction perpendicular to the magnetic steel guide rail 3 exceeds the range of the magnetic steel guide rail 3, so that the steering coil 6 is subjected to unilateral force, and steering is achieved by providing torque through the two steering coils 6.

[0030] The material of the coil carrier 4 is one or more non-magnetic polymer materials such as polyimide, polyphenylene sulfide, polyetheretherketone and polysulfone, which has no interference with magnetism during the operation of the motor.

[0031] The drive coil 5 and the steering coil 6 are bonded and cured in the frame of the coil carrier 4 by epoxy resin, so as to achieve seamless stitching of the coil (drive coil 5 and steering coil 6) and the coil carrier 4 and ensure accurate positioning and fixation of the drive coil 5 and the steering coil 6.

[0032] The inner sides of the two carrier connection plates 7 are respectively provided with a Hall sensor 10 and a grating ruler 11, and the Hall sensor 10 is connected to a host computer, and the host computer is electrically connected to the grating ruler 11. The Hall sensor 10 and the grating ruler 11 act as measuring elements during the motion process, output the magnetic field change as an electrical signal to the host computer for calculation, and then control the current of the driving coil 5 and the steering coil 6 to accurately control the motion process.

[0033] Therefore, the present invention adopts the above-mentioned three-degree-of-freedom magnetic levitation coreless linear motor, and utilizes the magnetic force between the permanent magnet and the coil to realize the suspension and drive of the motor rotor, thereby realizing low-friction or frictionless motion during the movement process, improving the stability of the motor during operation, reducing the pollution of the motor during the movement process, and realizing ultra-clean and very stable transportation of the motor, so as to be applied in wafer transportation, improve the cleanliness of the working area during wafer transportation, and ensure the quality of the wafer.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A three-degree-of-freedom magnetically suspended coreless linear motor, characterized in that: It includes a combined guide rail and an end cover arranged above the combined guide rail, the combined guide rail includes two magnetic steel guide rails, the two magnetic steel guide rails are connected by screws, the magnetic steel guide rails each include a plurality of magnetic steel blocks, two track side frames and a track bottom frame, the plurality of magnetic steel blocks are arranged at equal distances, the track side frames are symmetrically arranged on both sides of the magnetic steel blocks, the track bottom frame is arranged at the bottom of the magnetic steel blocks, a coil carrier is arranged between the two magnetic steel guide rails, a driving coil and a steering coil are arranged inside the coil carrier, carrier connectors are symmetrically arranged on both sides of the coil carrier, and the coil carrier and the carrier connector are connected by screws.

2. A three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The NS poles of the magnetic steel blocks are arranged alternately, and the magnetic lines of force are evenly distributed between the magnetic steel blocks on the upper and lower sides, and complete a closed loop inside the magnetic steel blocks.

3. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The width of the magnetic steel block is 30-50 mm, the height is 3-5 mm, and the spacing between two magnetic steel blocks is not less than 1 mm.

4. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The air gap height between the two magnetic steel guide rails is between 0.5 and 1.5 mm, and the gap height between the two magnetic steel guide rails and the coil carrier is between 0.3 and 0.5 mm.

5. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The outer side of the end cover is symmetrically provided with a slide groove, the inner side of the carrier connector is provided with a slider, the slide groove is adapted to the size of the slider, and the slide groove is slidably connected to the slider, and external connection threaded holes are provided above the end cover and on the outer side of the carrier connector.

6. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The winding method of the drive coil is bifilar winding or trifilar winding, the slot fill rate of the drive coil is not less than 60%, and the width of the drive coil is greater than the width of more than two even numbers of the magnetic steel blocks.

7. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The steering coil is wound in a double-wire or triple-wire manner, the slot fill rate of the steering coil is not less than 60%, and the width of the steering coil is less than the width of one magnetic steel block.

8. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The material of the coil carrier is one or more of polyimide, polyphenylene sulfide, polyetheretherketone and polysulfone.

9. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: The driving coil and the steering coil are bonded and cured in the frame of the coil carrier by epoxy resin.

10. The three-degree-of-freedom magnetically suspended coreless linear motor according to claim 1, characterized in that: A Hall sensor and a grating ruler are respectively arranged on the inner sides of the two carrier connection plates, the Hall sensor is connected to a host computer, and the host computer is electrically connected to the grating ruler.

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