CN118399700A - Two-degree-of-freedom motor with axial flux mover - Google Patents

Abstract

The invention provides a two-degree-of-freedom motor with an axial magnetic flux rotor, which comprises a rotary stator, a linear stator and a rotor, wherein the rotary stator and the linear stator are in a fan shape and have the same inner and outer diameters, and a cylindrical space is formed inside the rotary stator and the linear stator after buckling and combining; part of the rotor passes through the cylindrical space; the rotor comprises a plurality of annular rotor cores, a plurality of annular permanent magnet blocks, a rotating shaft and a bearing, wherein the annular rotor cores and the annular permanent magnet blocks are alternately arranged and sleeved on the rotating shaft through the bearing, outer teeth which are uniformly distributed are arranged on the outer peripheral surface of each annular rotor core, the outer teeth of the annular rotor core on one side of the same annular permanent magnet are opposite to the grooves between the annular rotor cores on the other side, and the annular permanent magnets on two sides of the same annular rotor core have different magnetic poles. The rotor structure adopts a structure with axially alternating arrangement of the whole permanent magnets, so that the rotor structure is compact in structure and high in material utilization rate, and the power density and efficiency are effectively increased while the axial magnetic flux working principle is realized.

Description

A two-degree-of-freedom motor with axial flux mover

Technical Field

The invention belongs to the technical field of special motors, and in particular relates to a two-degree-of-freedom motor with an axial flux mover.

Background technique

Motors can convert electrical energy into kinetic energy and are indispensable in the development of modern industry. Single-degree-of-freedom motors with one-dimensional motion cannot meet the requirements of complex drives. Therefore, two-degree-of-freedom motors are in great demand in industrial production. Two-degree-of-freedom motors are two-degree-of-freedom motors that can achieve linear, rotational and spiral motion. A variety of equipment such as robotic arms, spiral drilling machines, ship propulsion, spiral drilling machines, electric gyroscopes, etc. require the use of two-degree-of-freedom motors. With the increasing development of industrial manufacturing, the requirements for the accuracy of the drive system are also getting higher and higher.

The "two-degree-of-freedom induction motor" disclosed in Chinese patent 201320741315.2 is mainly composed of a stator and a mover. The invention uses a linear motion arc motor stator, a rotary motion arc motor stator and a solid mover. When driving the load to do rotation, linear or spiral motion, it has the advantages of simple structure and can eliminate radial force. However, it uses an induction motor, which has a lower power density than a permanent magnet motor, and has large eddy current losses, making it difficult to achieve high-precision position control, limiting the application of the motor.

The "rotating linear two-degree-of-freedom permanent magnet motor with stator and modular structure" disclosed in Chinese patent 202010059522.4 is mainly composed of a modular stator and a mover. The invention adopts multiple modular stator core units and a number of permanent magnet blocks and iron yoke rings that are alternately assembled. When driving the load to make rotational, linear or spiral motion, it has the advantages of high sinusoidal degree of back electromotive force and significantly improved torque/thrust density. However, the modular stator unit structure is lined up in rows, and the large number of modular stator units not only increases the difficulty of processing, but also increases the complexity of combined assembly.

Summary of the invention

In order to solve the problems of low power density and magnetic field coupling in the two-degree-of-freedom motor in the prior art and to reduce the difficulty of motor processing and assembly, the present invention discloses a two-degree-of-freedom motor with an axial flux mover, which adopts a rotating stator, a linear stator and two sets of independent armature windings, and can directly drive the load to perform linear, rotational or spiral motion. It has a compact structure, high material utilization, weak magnetic field coupling, high power density and easy control.

To achieve the above object, the technical solution of the present invention is as follows:

A two-degree-of-freedom motor with an axial flux mover comprises a rotating stator, a linear stator and a mover, wherein the rotating stator and the linear stator are both in the form of a sector ring and have equal inner and outer diameters, and a cylindrical space is formed inside the rotating stator and the linear stator after being interlocked and combined; a part of the mover passes through the cylindrical space; the rotating stator comprises a rotating stator core and a rotating winding; the rotating stator core is uniformly provided with trapezoidal semi-closed slots in the circumferential direction, the opening of the trapezoidal semi-closed slots faces the axis, the rotating winding is arranged in the trapezoidal semi-closed slots, pole shoes are provided between the trapezoidal semi-closed slots, and a plurality of uniformly distributed rectangular grooves are arranged along the circumferential direction on the bottom of the pole shoes facing the axis Open slots; the linear stator comprises a linear stator core and a linear winding, the linear stator core is provided with rectangular slots equidistantly along the axial direction, the rectangular slots open toward the axis, and the linear winding is arranged in the rectangular slots; the mover comprises a plurality of annular mover cores, a plurality of annular permanent magnet blocks, a rotating shaft and a bearing, the annular mover cores and the annular permanent magnet blocks are alternately arranged and sleeved on the rotating shaft through a bearing, the outer peripheral surface of each annular mover core is provided with uniformly distributed external teeth, the outer teeth of the annular mover core on one side of the same annular permanent magnet are opposite to the grooves between the teeth of the annular mover core on the other side, and the annular permanent magnets on both sides of the same annular mover core have different magnetic poles.

Furthermore, the size of the mover teeth is adapted to the size of the small teeth between the rectangular opening slots on the pole shoes of the rotating stator core, thereby improving the control accuracy.

Furthermore, the thickness of each annular mover core is equal, and the thickness of each annular permanent magnet block is equal.

Furthermore, the inner diameter of the annular mover core is the same as that of the annular permanent magnet block, and the outer edge of the annular permanent magnet block is flush with the bottom of the groove between the teeth of the annular mover core.

Furthermore, the opening widths of the rectangular open slot and the trapezoidal semi-closed slot are equal.

Furthermore, the bottom of the trapezoidal semi-closed groove is a curved surface.

Furthermore, the bottom of the rectangular opening groove is a plane.

Furthermore, the rotating stator core is formed by axially stacking silicon steel sheets of consistent shape.

Furthermore, the linear stator core is formed by circumferentially stacking silicon steel sheets of uniform shape.

The beneficial effects of the present invention are:

1. The mover structure of the present invention adopts a structure in which a whole permanent magnet is alternately arranged axially. While realizing the working principle of axial magnetic flux, it has a compact structure, high material utilization rate, and effectively increases power density and efficiency.

2. In the motor structure provided by the present invention, the two stators are arranged separately, and there is basically no magnetic field coupling in the main magnetic field, thereby reducing the magnetic field coupling strength.

3. The present invention uses two sets of windings to generate linear and rotating armature magnetic fields, and the magnetic flux paths of the linear winding and the rotating winding are perpendicular to each other, which can achieve better decoupled drive control of linear and rotating motions.

4. The permanent magnet and the rotor core of the present invention have simple structures, are easy to process, have compact structure of the mover, have small moment of inertia, and have little bearing wear.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the overall structure of a two-degree-of-freedom motor with an axial flux mover provided by the present invention.

FIG. 2 is an overall schematic diagram of a rotating stator.

FIG3 is an overall schematic diagram of a rotating winding.

FIG. 4 is an overall schematic diagram of a linear stator.

FIG5 is an overall schematic diagram of a linear winding.

FIG. 6 is a schematic diagram of the assembly of the mover core and the permanent magnet.

Figure 7 is a schematic diagram of the position of the mover core.

FIG8 is a schematic diagram of the side structure of the present invention.

List of Figure Symbols:

1. Rotating stator core; 11. Rectangular open slot; 12. Opening of trapezoidal semi-closed slot; 2. Rotating winding; 3. Linear stator core; 4. Linear winding; 5. Annular mover core; 51. First mover core, 52. Second mover core; 53. Third mover core; 512. Second mover outer teeth; 513. Third mover outer teeth; 6. Annular permanent magnet block; 7. Rotating shaft; 8. Bearing.

Detailed ways

The technical solution provided by the present invention will be described in detail below in conjunction with specific embodiments. It should be understood that the following specific implementation methods are only used to illustrate the present invention and are not used to limit the scope of the present invention.

As shown in FIG1 , a two-degree-of-freedom motor with an axial flux mover provided by the present invention is composed of a stator and a mover. The stator includes a rotating stator and a linear stator. The rotating stator and the linear stator are both fan-shaped with equal inner and outer diameters, and they are interlocked up and down to form a roughly circular ring, and a cylindrical space is formed inside. The mover passes through the cylindrical space formed by the stator buckling.

Specifically, the rotating stator is composed of a rotating stator core 1 and a centralized rotating winding 2. As shown in the three-dimensional schematic diagram of Figure 2, the rotating stator core 1 is in the shape of an "arch bridge" (or fan ring). The rotating stator core is formed by axially stacking silicon steel sheets of uniform shape; the rotating stator core is evenly opened with trapezoidal semi-closed slots in the circumference, and the bottom of the slot (the side close to the outer circumference of the stator is the bottom) is arc-shaped, and the bottom of the pole shoe is circumferentially provided with evenly distributed rectangular open slots 11, and the bottom of the slot is a plane. The rectangular open slot opens toward the axis. The rectangular open slot 11 and the opening 12 of the trapezoidal semi-closed slot play a modulation role together. In this example, the rectangular open slot 11 is as wide as the opening 12 of the trapezoidal semi-closed slot. The slot width of the rectangular open slot 11 and the width of the opening 12 of the trapezoidal semi-closed slot may also be unequal, and can be adjusted as needed. The overall shape of the rotating winding 2 is shown in FIG. 3 . The rotating winding 2 is arranged in the trapezoidal semi-closed slots of the rotating stator core, that is, it is axially wound on the parallel teeth between the trapezoidal semi-closed slots.

The linear stator is composed of a linear stator core 3 and a linear winding 4. As shown in the three-dimensional schematic diagram of Figure 4, the linear stator core 3 is in the shape of an "arch bridge" (or fan ring). The linear stator core is made of silicon steel sheets of the same shape stacked in the circumferential direction; the linear stator core has rectangular slots equidistantly opened in the axial direction, and the bottom is arc-shaped. The overall shape of the linear winding is shown in Figure 5, which is centrally arranged in the slots of the linear stator core, specifically, it is wound on the rotating stator teeth (the stator teeth are between the rectangular slots) along the axial direction of the slots. The number of linear stator slots is adapted to the size of the rotor.

As shown in Figures 6 and 7, the mover is composed of a number of annular mover cores 5, a number of annular permanent magnet blocks 6, a rotating shaft 7 and a bearing 8. Among them, the annular mover cores 5 and the annular permanent magnet blocks 6 are arranged alternately, and together constitute the main structure of the mover. The annular mover core 5 has the same inner diameter as the annular permanent magnet block 6, the outer diameter of the annular permanent magnet block 6 is equivalent to the outer diameter of the annular mover core 5, and the outer edge of the annular permanent magnet block 6 is flush with the bottom of the annular mover core 5 slot. The thickness of the annular mover core and the permanent magnet block can be designed according to performance requirements. The outer peripheral surface of each annular mover core 5 is provided with external teeth evenly distributed in the circumference, and slots are formed between the external teeth. The width of the external teeth of the mover core is equal to the width of the slot. The spacing and height of the external teeth of the mover core are adapted to the width of the rotating stator slot opening 11 and the slot opening 12, which plays a role in modulating harmonics. Specifically, the first mover core 51 closest to the viewing angle in FIG7 is staggered by a mover tooth slot angle with the adjacent second mover core 52 (the adjacent mover cores are separated by an annular permanent magnet block) in the circumferential direction, and the teeth of the first mover core 51 correspond to the slots of the adjacent second mover core 52. In the figure, the first mover outer teeth 511 on the first mover core 51 are staggered by a tooth width with the second mover outer teeth 512 on the adjacent second mover core 52. The second mover core 52 is staggered by a mover tooth slot angle with the adjacent third mover core 53 in the circumferential direction, and the slots of the second mover core 52 correspond to the teeth of the adjacent third mover core 53. Specifically, the second mover outer teeth 512 on the second mover core 52 are staggered by a tooth width with the third mover outer teeth 513 on the adjacent third mover core 53. In sequence, the adjacent mover cores are staggered by a tooth width to form a relative structure of adjacent mover core tooth slots.

The annular permanent magnet block 6 is magnetized axially. The magnetization of the two annular permanent magnet blocks 6 adjacent to the mover is opposite, the thickness of each annular permanent magnet block 6 is equal, and the thickness of each annular mover core is also equal to ensure the stable operation of the motor. The thickness of each adjacent mover core and permanent magnet block can be determined according to different motor performance design requirements. As shown in Figure 6.

The two stators are connected to form a circular cylindrical motor stator through plastic sealing and other technologies, with a gap between the two stators to ensure insulation. The annular mover core 5 and the annular permanent magnet block 6 are alternately arranged and sleeved on the rotating shaft 7, and are arranged in the cylindrical space inside the rotating stator and the linear stator through the bearing 8. The bearing 8 is a two-degree-of-freedom bearing, and the mover can perform rotation, linear and spiral motion under the support of the bearing 8.

When only the rotating winding 2 is supplied with alternating current, the magnetic field generated by the rotating stator and the circumferential magnetic field generated by the mover drive the mover to rotate; when only the linear winding 4 is supplied with alternating current, the magnetic field generated by the stator and the axial magnetic field generated by the mover drive the mover to move linearly. When alternating current is supplied to both the rotating stator winding and the linear stator winding, two different magnetic fields are generated at the same time, which can drive the motion axis to rotate, move linearly, and move in a spiral motion.

It should be noted that the above content merely illustrates the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims (9)

1. A two degree of freedom motor having an axial flux mover, characterized by: the rotary stator and the linear stator are in a fan shape and have the same inner diameter and outer diameter, and a cylindrical space is formed inside the rotary stator and the linear stator after the rotary stator and the linear stator are buckled and combined; part of the mover passes through the cylindrical space; the rotary stator comprises a rotary stator core and a rotary winding; the stator core is uniformly provided with trapezoid semi-closed grooves in the circumferential direction, the trapezoid semi-closed grooves are opened towards the axle center, the rotary winding is arranged in the trapezoid semi-closed grooves, pole shoes are arranged between the trapezoid semi-closed grooves, and a plurality of rectangular open grooves which are uniformly distributed are arranged in the circumferential direction towards the bottom of the axle center of the pole shoes; the linear stator comprises a linear stator iron core and a linear winding, wherein rectangular grooves are formed in the linear stator iron core at equal intervals along the axial direction, the rectangular grooves are opened towards the axle center, and the linear winding is arranged in the rectangular grooves; the rotor comprises a plurality of annular rotor cores, a plurality of annular permanent magnet blocks, a rotating shaft and a bearing, wherein the annular rotor cores and the annular permanent magnet blocks are alternately arranged and sleeved on the rotating shaft through the bearing, outer teeth which are uniformly distributed are arranged on the outer peripheral surface of each annular rotor core, the outer teeth of the annular rotor core on one side of the same annular permanent magnet are opposite to the grooves between the annular rotor cores on the other side, and the annular permanent magnets on two sides of the same annular rotor core have different magnetic poles.

2. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the rotor tooth size is matched with the small tooth size between rectangular open slots on the pole shoe of the rotary stator core.

3. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the thickness of each annular rotor core is equal, and the thickness of each annular permanent magnet block is equal.

4. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the inner diameters of the annular rotor core and the annular permanent magnet block are the same, and the outer edges of the annular permanent magnet block are flush with the bottoms of the grooves between the teeth of the annular rotor core.

5. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the rectangular open slot and the trapezoid semi-closed slot have the same opening width.

6. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the bottom of the trapezoid semi-closed groove is an arc surface.

7. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the bottom of the rectangular open slot is a plane.

8. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the rotary stator core is formed by axially laminating silicon steel sheets with the same shape.

9. The two-degree-of-freedom motor with axial flux mover of claim 1 wherein: the linear stator core is formed by circumferentially laminating silicon steel sheets with the same shape.