CN108736675B - Moving-coil type unipolar permanent magnet rotary linear motor - Google Patents
Moving-coil type unipolar permanent magnet rotary linear motor Download PDFInfo
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- CN108736675B CN108736675B CN201810726754.3A CN201810726754A CN108736675B CN 108736675 B CN108736675 B CN 108736675B CN 201810726754 A CN201810726754 A CN 201810726754A CN 108736675 B CN108736675 B CN 108736675B
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- 238000004804 winding Methods 0.000 claims description 35
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 claims description 3
- 229910001172 neodymium magnet Inorganic materials 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 4
- 239000004020 conductor Substances 0.000 description 4
- 238000005299 abrasion Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000005461 lubrication Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000012994 industrial processing Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K16/00—Machines with more than one rotor or stator
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K41/00—Propulsion systems in which a rigid body is moved along a path due to dynamo-electric interaction between the body and a magnetic field travelling along the path
- H02K41/02—Linear motors; Sectional motors
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Electromagnetism (AREA)
- Linear Motors (AREA)
Abstract
The invention discloses a moving-coil type unipolar permanent magnet rotary linear motor which comprises a cylindrical outer stator, a front end cover and a rear end cover which are fixed at two ends of the outer stator, and an extension shaft movably arranged in the outer stator. The extension shaft is fixed with a limited angle rotor and a linear motion secondary. An inner stator fixedly connected with the rear end cover is arranged in the linear motion secondary stage. The limited angle rotor acts with the outer stator, and the linear motion secondary acts with the outer stator and the inner stator simultaneously, so that the linear motion, the limited angle motion and the spiral motion of the extending shaft passing through are realized. The motor has the advantages of simple and compact structure, reduces the consumption of the permanent magnet, improves the air gap density, and has the characteristics of simple control, small mutual influence of linear thrust and rotation torque and the like.
Description
Technical Field
The invention relates to the field of rotary linear permanent magnet motors, in particular to a moving-coil type unipolar permanent magnet rotary linear motor.
Background
Conventional motors generally provide only a single degree of freedom motion (rotational or linear), but cannot achieve a combined rotational and linear motion. However, in robotic joints, industrial production, processing, and assembly systems, multiple freedoms are often required. Typically, this multiple degree of freedom motion is achieved by mechanical stitching of the basic elements that can perform either linear or rotational motion, but this approach has the following problems: first, because the functional parts are mixed with mechanical elements, friction, abrasion and deformation are serious; second, the rotational motion and the linear motion are coupled and cannot be independently controlled; third, the accuracy of such actuators is limited by machining; fourth, the use of multiple motors for control not only increases the volume and weight of the device, but also presents inconvenience for control. With the development of science and technology, electromechanical systems are increasingly complex, and especially, requirements of precise devices such as a die bonder, a bonding machine, a PCB drilling machine and the like on driving performance are increasingly high, and the requirements of the devices such as control precision and response time and the like realized by mechanically combining rotary motion units and linear motion units cannot be met.
Chinese patent 201410448886.6 discloses a rotary linear permanent magnet motor, which adopts a unipolar permanent magnet, and sequentially comprises, from inside to outside in a radial direction, an inner rotor shaft, an air bearing, an annular protruding portion of a supporting seat, a rotor core, a rotor permanent magnet, a linear armature winding, a rotary armature winding and a stator core, so that an equivalent air gap is greatly increased, an air gap flux density is effectively reduced, and an axial attractive force exists in the motor structure due to a moving magnet structure. Chinese patent 201020582357.2 discloses a high-frequency linear rotary motor, the linear motion part and the rotary motion part of which are a voice coil motor and a rotary servo motor, respectively. Essentially, the motor is an integrated linear rotation two-degree-of-freedom motor which is not truly installed together, and has larger volume. Chinese patent 201510282204.3 discloses a linear rotary permanent magnet actuator employing a staggered pole structure, in which three groups of stator units are axially arranged, and the three groups of stator units are connected by a non-magnetic connector, and the mover is axially arranged with opposite magnetic poles alternately, so that the amount of permanent magnets is effectively reduced, but complex control is brought.
Disclosure of Invention
In view of the current state of the art, the invention aims to provide a moving-coil type unipolar permanent magnet rotary linear motor which has the advantages of simple and compact structure, reduces the dosage of the permanent magnet, improves the air gap flux density, and has the characteristics of simple control, small mutual influence of linear thrust and rotary torque and the like.
The technical scheme of the invention is as follows: a moving-coil type unipolar permanent magnet rotary linear motor comprises a cylindrical outer stator, front end covers and rear end covers fixed at two ends of the outer stator, and a protruding shaft movably arranged in the outer stator. The extension shaft is fixed with a limited angle rotor and a linear motion secondary. An inner stator fixedly connected with the rear end cover is arranged in the linear motion secondary stage. The limited angle rotor acts with the outer stator, and the linear motion secondary acts with the outer stator and the inner stator simultaneously, so that the linear motion, the limited angle motion and the spiral motion of the extending shaft passing through are realized.
The extending shaft is provided with a first fixing part and a second fixing part along the axial direction, the front end of the first fixing part is in running fit with the first sleeve on the front end cover, and the limited-angle rotor is arranged on the first fixing part. The second fixing part is cylindrical, the linear motion secondary is fixedly connected with the second fixing part, and the inner stator is positioned in the linear motion secondary.
The rear end cap has a mounting shaft extending into the second fixing portion. The inner stator is fixed on the installation shaft. The mounting shaft is provided with a second sleeve matched with the inner wall of the second fixing part.
The limited angle rotor is composed of a rotor core with teeth and a rotary armature winding. The outer stator consists of a toothed stator core and a unipolar permanent magnet.
The linear motion secondary consists of a linear armature winding and a winding framework. The winding framework is cylindrical, and the end part of the winding framework is coaxially connected with the end part of the second fixing part.
The unipolar permanent magnet and the inner stator are homopolar neodymium-iron-boron permanent magnets, and the magnetizing direction is radial magnetizing.
The number p of the unipolar permanent magnets and the number Q of the teeth of the toothed stator core meet the pole slot matching requirement of the three-phase permanent magnet motor.
The linear armature winding is a circular coil and is arranged on the outer wall of the winding framework. The rotary armature winding is concentrated winding, and is embedded between teeth of the rotor core.
The end cover is made of magnetic conductive material, and the extension shaft is made of non-magnetic conductive material.
The tooth portion of the stator core occupies an angle tau c And angle tau occupied by a unipolar permanent magnet pm The ratio is: 0.5 to 1.5.
The beneficial effects of the invention are as follows: the movable coil type unipolar permanent magnet rotary linear motor adopts the shared outer stator, and the rotary armature winding and the linear armature winding are arranged in the axial direction, so that under the action of an excitation magnetic field of the unipolar permanent magnet, the moment for driving the rotor to rotate can be generated, the linear thrust for driving the rotor to linearly move can also be generated, and the moment for driving the rotor to rotate and the linear thrust for driving the rotor to linearly move can also be simultaneously generated, thereby driving the rotor to perform spiral movement and realizing the two-degree-of-freedom movement of the rotor; and the mutual influence of the linear thrust and the rotation torque is small, so that the decoupling control of the rotation and the linear motion can be conveniently realized. The structure not only solves the problems of low efficiency, easy abrasion, difficult lubrication and the like caused by the prior art that the mechanical part conversion and the multiple-degree-of-freedom motion mode are realized by a plurality of motors, but also improves the torque density and the axial attraction-free advantage of the motors, and effectively improves the precision and the efficiency of the whole production operation.
Drawings
Fig. 1 is a schematic sectional view of a moving coil type unipolar permanent magnet rotary linear motor according to the present embodiment.
Fig. 2 is a schematic structural view of a limited angle rotor in the present embodiment.
Fig. 3 is a schematic cross-sectional structure of the outer stator in the present embodiment.
Fig. 4 is a schematic cross-sectional view of the primary linear motion in this embodiment.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
Fig. 1 to 4 are schematic structural views of the present invention.
Wherein the reference numerals are as follows: the stator comprises an outer stator 1, a stator core 11, a unipolar permanent magnet 12, a limited-angle rotor 2, a rotor core 21, a rotary armature winding 22, a linear motion secondary 3, a linear armature winding 31, a winding frame 32, an extension shaft 4, a front end cover 5, a rear end cover 6, an inner stator 7, a first sleeve 81 and a second sleeve 82.
The moving coil type unipolar permanent magnet rotary linear motor of the embodiment comprises a cylindrical outer stator 1, front end covers 5 and rear end covers 6 fixed at two ends of the outer stator 1, and an extension shaft 4 movably arranged in the outer stator 1.
The limited angle rotor 2 and the linear motion secondary 3 are fixed on the extension shaft 4. An inner stator 7 fixedly connected with the rear end cover 6 is arranged in the linear motion secondary 3. The limited angle rotor 2 is coupled with the outer stator 1, and the linear motion secondary 3 interacts with the outer stator 1 and the inner stator 7 simultaneously, so that the linear motion, the limited angle motion and the spiral motion of the extension shaft 4 passing through are realized.
The extending shaft 4 is provided with a first fixing part and a second fixing part along the axial direction, the front end of the first fixing part is in running fit with a first sleeve 81 on the front end cover 5, and the limited-angle rotor 2 is arranged on the first fixing part. The second fixing part is cylindrical, the linear motion secondary 3 is fixedly connected with the second fixing part, and the inner stator 7 is positioned in the linear motion secondary 3.
The rear end cap 6 has a mounting shaft extending into the second fixing portion. The inner stator 7 is fixed on the mounting shaft. The mounting shaft is provided with a second sleeve 82 which is fitted to the inner wall of the second fixing portion.
As shown in fig. 2, the limited angle rotor 2 is composed of a rotor core 21 with teeth and a rotary armature winding 22. The outer stator 1 consists of a toothed stator core 11 and a unipolar permanent magnet 12.
The rotary armature winding 22 and the linear armature winding 31 are axially distributed on the extension shaft 4, and under the action of the exciting magnetic field of the unipolar permanent magnet, the moment for driving the rotor 2 to rotate can be generated, the linear thrust for driving the secondary 3 to linearly move can also be generated, and the moment for driving the extension shaft 4 to rotate and the linear thrust for driving the extension shaft 4 to linearly move can also be simultaneously generated, so that the extension shaft 4 is driven to perform spiral movement, and the two-degree-of-freedom movement of the extension shaft 4 is realized
The linear motion secondary 3 is composed of a linear armature winding 31 and a winding former 32. The bobbin 32 is cylindrical, and an end of the bobbin 32 is coaxially connected to an end of the second fixing portion.
The unipolar permanent magnet 12 and the inner stator 7 are homopolar neodymium-iron-boron permanent magnets, and the magnetizing direction is radial magnetizing.
The number p of the unipolar permanent magnets 12 and the number Q of the teeth of the toothed stator core 11 meet the pole slot matching requirement of the three-phase permanent magnet motor.
As shown in fig. 4, the linear armature winding 31 is a toroidal coil, and is mounted on the outer wall of the bobbin 32. The rotary armature winding 22 is a concentrated winding, and the rotary armature winding 22 is embedded between teeth of the rotor core 21.
In this embodiment, the end cap 6 is made of a magnetically conductive material, and the protruding shaft 4 is made of a non-magnetically conductive material.
As shown in fig. 3, the teeth of the stator core 11 occupy an angle τ c And the angle tau occupied by the unipolar permanent magnets 12 pm The ratio is: 0.5 to 1.5.
The moving-coil type unipolar permanent magnet rotary linear motor not only solves the problems of low efficiency, easiness in abrasion, difficulty in lubrication and the like caused by the fact that the prior art depends on mechanical component conversion and a multi-degree-of-freedom motion mode realized by a plurality of motors, but also improves the torque density and the advantages of no axial attraction of the motors, and effectively improves the precision and the efficiency of the whole production operation.
The preferred embodiments of this invention have been described so far that various changes or modifications may be made by one of ordinary skill in the art without departing from the scope of this invention.
Claims (6)
1. A moving coil type unipolar permanent magnet rotary linear motor is characterized in that: comprises a cylindrical outer stator (1), a front end cover (5) and a rear end cover (6) which are fixed at two ends of the outer stator (1), and an extension shaft (4) which is movably arranged in the outer stator (1); the limited-angle rotor (2) and the linear motion secondary (3) are fixed on the extension shaft (4); an inner stator (7) fixedly connected with the rear end cover (6) is arranged in the linear motion secondary (3); the limited angle rotor (2) acts with the outer stator (1), and the linear motion secondary (3) acts with the outer stator (1) and the inner stator (7) simultaneously, so that the linear motion, the limited angle motion and the spiral motion of the extension shaft (4) passing through are realized;
the extension shaft (4) is provided with a first fixing part and a second fixing part along the axial direction, the front end of the first fixing part is in running fit with a first sleeve (81) on the front end cover (5), and the limited-angle rotor (2) is arranged on the first fixing part; the second fixing part is cylindrical, the linear motion secondary (3) is fixedly connected with the second fixing part, and the inner stator (7) is positioned in the linear motion secondary (3);
the rear end cover (6) is provided with a mounting shaft extending to the inside of the second fixing part; the inner stator (7) is fixed on the mounting shaft; the mounting shaft is provided with a second sleeve (82) matched with the inner wall of the second fixing part;
the limited-angle rotor (2) consists of a rotor core (21) with teeth and a rotary armature winding (22); the outer stator (1) consists of a stator core (11) with teeth and a unipolar permanent magnet (12);
the linear motion secondary (3) consists of a linear armature winding (31) and a winding framework (32); the winding framework (32) is cylindrical, and the end part of the winding framework (32) is coaxially connected with the end part of the second fixing part.
2. The moving coil type unipolar permanent magnet rotary linear motor of claim 1, wherein: the unipolar permanent magnet (12) and the inner stator (7) are homopolar neodymium-iron-boron permanent magnets, and the magnetizing direction is radial magnetizing.
3. The moving coil type unipolar permanent magnet rotary linear motor of claim 1, wherein: the number p of the unipolar permanent magnets (12) and the number Q of teeth of the toothed stator core (11) meet the pole slot matching requirement of the three-phase permanent magnet motor.
4. The moving coil type unipolar permanent magnet rotary linear motor of claim 1, wherein: the linear armature winding (31) is a circular coil and is arranged on the outer wall of the winding framework (32); the rotary armature winding (22) is a concentrated winding, and the rotary armature winding (22) is embedded between teeth of the rotor core (21).
5. The moving coil type unipolar permanent magnet rotary linear motor of claim 1, wherein: the rear end cover (6) is made of magnetic conduction materials, and the extension shaft (4) is made of non-magnetic conduction materials.
6. The moving coil type unipolar permanent magnet rotary linear electric device according to claim 1The machine is characterized in that: the tooth portion of the stator core (11) occupies an angle tau c And the angle tau occupied by the unipolar permanent magnet (12) pm The ratio is: 0.5 to 1.5.
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CN201810726754.3A CN108736675B (en) | 2018-07-05 | 2018-07-05 | Moving-coil type unipolar permanent magnet rotary linear motor |
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CN201810726754.3A CN108736675B (en) | 2018-07-05 | 2018-07-05 | Moving-coil type unipolar permanent magnet rotary linear motor |
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CN108736675B true CN108736675B (en) | 2023-11-14 |
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CN110112882A (en) * | 2019-06-04 | 2019-08-09 | 浙江江宇电机有限公司 | A kind of motor of exportable compound motion |
CN113315331B (en) * | 2021-07-28 | 2021-10-26 | 深圳双十科技有限公司 | Two-degree-of-freedom motor for Z axis and assembling method thereof |
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