CN108736675B - Moving-coil type unipolar permanent magnet rotary linear motor - Google Patents

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

A moving coil unipolar permanent magnet rotating linear motor

Technical field

The present invention relates to the field of rotating linear permanent magnet motors, specifically a moving coil type unipolar permanent magnet rotating linear motor.

Background technique

Traditional motors generally can only provide single degree of freedom motion (rotary motion or linear motion), but cannot achieve compound motion of rotation and linear motion. However, in systems such as robot joints, industrial production, processing and assembly, it is often necessary to achieve multiple free movements. Usually, this kind of multi-degree-of-freedom motion is realized through mechanical splicing and combination of basic elements that can perform linear or rotational motion. However, this method has the following problems: First, because its functional components are mixed with mechanical elements, Its friction, wear and deformation are relatively serious; secondly, the rotational motion and linear motion are coupled and cannot be controlled independently; thirdly, the accuracy of this actuator is limited by mechanical processing; fourthly, the use of multiple motors for control Not only will it increase the size and weight of the equipment, but it will also cause inconvenience to control. Moreover, with the development of science and technology, electromechanical systems are becoming increasingly complex, especially some precision devices, such as die bonding machines, bonding machines, PCB drilling, etc., which have increasingly higher requirements for driving performance. By mechanically combining rotation The performance of device control accuracy and response time achieved by motion and linear motion units can no longer meet their needs.

Chinese patent 201410448886.6 discloses a rotating linear permanent magnet motor. The motor uses unipolar permanent magnets. From the inside to the outside in the radial direction, they are the rotor inner shaft, the air bearing, the annular protrusion of the support seat, and the rotor core. , rotor permanent magnets, linear armature windings, rotating armature windings and stator core, which greatly increases the equivalent air gap and effectively reduces the air gap magnetic density. Moreover, due to the moving magnet structure, the motor structure has axial attraction. Chinese patent 201020582357.2 discloses a high-frequency linear rotary motor. The linear motion part and the rotary motion part of the motor are a voice coil motor and a rotary servo motor respectively. Essentially, this motor is a two-degree-of-freedom motor installed together. It is not a true integrated linear rotation two-degree-of-freedom motor and is relatively large. Chinese patent 201510282204.3 discloses a linear rotating permanent magnet actuator with a staggered pole structure. The actuator is equipped with three sets of stator units in the axial direction, and the three sets of stator units are connected through non-magnetic connectors, and the mover Opposite magnetic poles are alternately arranged in the axial direction, which effectively reduces the amount of permanent magnets, but brings complicated control.

Contents of the invention

In view of the current status of the existing technology, the purpose of the present invention is to provide a moving coil unipolar permanent magnet rotating linear motor, which has the advantages of simple and compact structure, reduces the amount of permanent magnets, and improves the air gap magnetic density. It has the characteristics of simple control, small interaction between linear thrust and rotation torque.

The technical solution of the present invention is as follows: a moving coil type unipolar permanent magnet rotating linear motor, including a cylindrical outer stator, a front end cover and a rear end cover fixed at both ends of the outer stator, and an extended shaft movable inside the outer stator. . A limited-angle rotor and a linear motion secondary are fixed on the extended shaft. There is an inner stator fixedly connected to the rear end cover inside the linear motion secondary. The limited-angle rotor interacts with the outer stator, and the linear motion secondary acts with the outer and inner stators simultaneously to realize linear motion, limited angle motion and spiral motion through which the extended shaft passes.

The above-mentioned extending shaft has a first fixed part and a second fixed part distributed along the axial direction. The front end of the first fixed part rotates with the first sleeve on the front end cover, and the limited-angle rotor is installed on the first fixed part. The second fixed part is cylindrical, the linear motion secondary is fixedly connected to the second fixed part, and the inner stator is located inside the linear motion secondary.

The above-mentioned rear end cover has an installation shaft extending to the inside of the second fixing part. The inner stator is fixed on the mounting shaft. The installation shaft is provided with a second sleeve that matches the inner wall of the second fixing part.

The above-mentioned limited-angle rotor consists of a rotor core with teeth and a rotating armature winding. The outer stator consists of a toothed stator core and unipolar permanent magnets.

The above-mentioned linear motion secondary consists of a linear armature winding and a winding skeleton. The winding bobbin is cylindrical, and the end of the winding bobbin is coaxially connected to the end of the second fixing part.

The above-mentioned unipolar permanent magnets and the inner stator are both NdFeB permanent magnets of the same polarity, and the magnetizing direction is radial magnetization.

The number p of the above-mentioned unipolar permanent magnets and the number Q of teeth of the toothed stator core meet the pole slot matching requirements of the three-phase permanent magnet motor.

The above-mentioned linear armature winding is an annular coil and is installed on the outer wall of the winding frame. The rotating armature winding is a concentrated winding, and the rotating armature winding is embedded between the teeth of the rotor core.

The above-mentioned end cover is made of magnetically conductive material, and the extended shaft is made of non-magnetic conductive material.

The ratio between the angle τ _c occupied by the teeth of the stator core and the angle τ _pm occupied by the unipolar permanent magnet is: 0.5 to 1.5.

The beneficial effects of the present invention are: the moving coil type unipolar permanent magnet rotating linear motor of the present invention adopts a common outer stator, and by arranging the rotating armature winding and the linear armature winding in the axial direction, the unipolar permanent magnet Under the action of the excitation magnetic field, it can generate a torque that drives the rotor to rotate, and it can also generate a linear thrust that drives the rotor to move linearly. It can also generate a torque that drives the rotor to rotate and a linear thrust that drives the rotor to move linearly, thereby driving the rotor to perform spiral motion. It realizes two degrees of freedom motion of the rotor; and the linear thrust and rotational torque have little influence on each other, so it is easy to realize decoupling control of rotation and linear motion. This structure not only solves many problems such as low efficiency, easy wear, and difficulty in lubrication caused by the multi-degree-of-freedom movement method achieved by the existing technology relying on mechanical component conversion and multiple motors, but also improves the torque density of the motor and the shaftless The attractive advantages effectively improve the accuracy and efficiency of the entire production operation.

Description of the drawings

Figure 1 is a schematic cross-sectional structural diagram of a moving coil type unipolar permanent magnet rotating linear motor in this embodiment.

Figure 2 is a schematic structural diagram of the limited-angle rotor in this embodiment.

Figure 3 is a schematic cross-sectional structural diagram of the outer stator in this embodiment.

Figure 4 is a schematic cross-sectional structural diagram of the linear motion primary in this embodiment.

Detailed ways

The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Figures 1 to 4 show schematic structural diagrams of the present invention.

The reference numbers are: outer stator 1, stator core 11, unipolar permanent magnet 12, limited angle rotor 2, rotor core 21, rotating armature winding 22, linear motion secondary 3, linear armature winding 31, winding Frame 32, extended shaft 4, front end cover 5, rear end cover 6, inner stator 7, first sleeve 81, second sleeve 82.

The moving coil type unipolar permanent magnet rotating linear motor of this embodiment includes a cylindrical outer stator 1, a front end cover 5 and a rear end cover 6 fixed at both ends of the outer stator 1, and an extending shaft movable inside the outer stator 1. 4.

A limited-angle rotor 2 and a linear motion secondary 3 are fixed on the extended shaft 4. An inner stator 7 fixedly connected to the rear end cover 6 is provided inside 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 to realize linear motion, limited angle motion and spiral motion through which the extended shaft 4 passes.

The extended shaft 4 has a first fixed part and a second fixed part distributed along the axial direction. The front end of the first fixed part rotates with the first sleeve 81 on the front end cover 5. The limited-angle rotor 2 is installed on the first fixed part. . The second fixed part is cylindrical, the linear motion secondary 3 is fixedly connected to the second fixed part, and the inner stator 7 is located inside the linear motion secondary 3 .

The rear end cover 6 has a mounting shaft extending to the inside of the second fixing part. The inner stator 7 is fixed on the installation shaft. The mounting shaft is provided with a second sleeve 82 that matches the inner wall of the second fixing part.

As shown in FIG. 2 , the limited-angle rotor 2 is composed of a rotor core 21 with teeth and a rotating armature winding 22 . The outer stator 1 is composed of a toothed stator core 11 and a unipolar permanent magnet 12 .

The rotating armature winding 22 and the linear armature winding 31 are axially distributed on the extended shaft 4. Under the action of the unipolar permanent magnet excitation magnetic field, they can generate a torque that drives the rotor 2 to rotate, and can also generate a linear motion secondary drive. 3 The linear thrust of the linear motion can also simultaneously generate the torque that drives the extension shaft 4 to rotate and the linear thrust that drives the extension shaft 4 to move linearly, thereby driving the extension shaft 4 to perform spiral motion, realizing the two freedoms of the extension shaft 4 degree movement

The linear motion secondary 3 consists of a linear armature winding 31 and a winding skeleton 32. The winding bobbin 32 is cylindrical, and the end of the winding bobbin 32 is coaxially connected to the end of the second fixing part.

The unipolar permanent magnet 12 and the inner stator 7 are both NdFeB permanent magnets of the same polarity, and the magnetizing direction is radial magnetization.

The number p of unipolar permanent magnets 12 and the number Q of teeth of the toothed stator core 11 meet the pole slot matching requirements of the three-phase permanent magnet motor.

As shown in FIG. 4 , the linear armature winding 31 is a circular coil and is installed on the outer wall of the winding frame 32 . The rotating armature winding 22 is a concentrated winding, and the rotating armature winding 22 is embedded between the teeth of the rotor core 21 .

In this embodiment, the end cover 6 is made of magnetically conductive material, and the extending shaft 4 is made of non-magnetic conductive material.

As shown in FIG. 3 , the ratio between the angle τ _c occupied by the teeth of the stator core 11 and the angle τ _pm occupied by the unipolar permanent magnet 12 is: 0.5 to 1.5.

The moving coil type unipolar permanent magnet rotating linear motor of this embodiment not only solves many problems such as low efficiency, easy wear, and difficulty in lubrication caused by the multi-degree-of-freedom motion mode achieved by the existing technology relying on mechanical component conversion and multiple motors. , also improves the torque density of the motor and the advantages of no axial attraction, effectively improving the accuracy and efficiency of the entire production operation.

The preferred embodiments of the present invention have been clarified, and various changes or modifications may be made by those of ordinary skill in the art without departing from the scope of the present 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.