CN116526801A - Linear motor and linear compressor - Google Patents

Abstract

The present disclosure relates to a linear motor including a mover permanent magnet, an outer stator core, and a stator winding coil; the stator winding coils are two groups, the two groups of stator winding coils are arranged on the outer stator core at intervals, and the winding directions of the two groups of stator winding coils are opposite; the rotor permanent magnet is arranged on the inner side of the outer stator core; the rotor permanent magnet is an axial magnetizing permanent magnet, two ends of the rotor permanent magnet in the axial direction are respectively provided with a magnetizer, the rotor permanent magnet can linearly reciprocate along the axial direction of the outer stator core under the action of magnetic force generated by energizing the stator winding coil, and the inner stator core is not needed, so that the motor is more compact in structure, the occupied space of the motor is reduced, and meanwhile, the efficiency of the motor is guaranteed.

Description

Linear motor and linear compressor

Technical Field

The disclosure relates to the technical field of motors, and in particular relates to a linear motor and a linear compressor.

Background

The linear compressor is a main device for compressing working media such as gas.

The linear compressor includes: the linear motor drives the piston to linearly reciprocate in the cylinder sleeve, so that the compression of working media is realized. Wherein, linear electric motor specifically includes: an outer stator core, an inner stator core, and a mover permanent magnet; the inner stator core is positioned at the inner side of the outer stator core, the mover permanent magnet is a radial magnetizing permanent magnet, the mover permanent magnet is positioned between the outer stator core and the inner stator core, and the mover permanent magnet is connected with the piston. The rotor permanent magnet drives the piston to reciprocate in the cylinder sleeve under the action of magnetic force generated by electrifying a winding coil wound on the outer stator core.

However, the above-mentioned linear motor is not compact enough in structure, resulting in a large occupied space of the motor and, in turn, a large volume of the linear compressor using the same.

Disclosure of Invention

In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a linear motor and a linear compressor.

In a first aspect, the present disclosure provides a linear motor, including a mover permanent magnet, an outer stator core, and a stator winding coil wound on the outer stator core;

the stator winding coils are arranged in two groups, the two groups of stator winding coils are arranged on the outer stator iron core at intervals, and the winding directions of the two groups of stator winding coils are opposite;

the rotor permanent magnet is arranged on the inner side of the outer stator core; the rotor permanent magnet is an axial magnetizing permanent magnet, two axial ends of the rotor permanent magnet are respectively provided with a magnetizer, and the rotor permanent magnet can linearly reciprocate along the axial direction of the outer stator core under the action of magnetic force generated by energizing the stator winding coil;

wherein the outer diameter of the magnetizer is not smaller than the outer diameter of the mover permanent magnet.

Optionally, at least one of the magnetizers at two ends of the mover permanent magnet is an iron core ring arranged at the end part of the mover permanent magnet.

Optionally, the magnetizer is attached to the mover permanent magnet.

Optionally, the length of the mover permanent magnet in the axial direction is greater than the interval distance between the inner sides of the two groups of stator winding coils.

Optionally, when the stator winding coils are not electrified, the position of the mover permanent magnet in the axial direction is located between two groups of the stator winding coils.

Optionally, a pole shoe is disposed on a side of the outer stator core, which is close to the mover permanent magnet, and the pole shoe is located at two ends of the stator winding coil in the axial direction.

Optionally, the pole shoe and the outer stator core are integrally formed.

In a second aspect, the present disclosure provides a linear compressor comprising a cylinder liner, a piston, and a linear motor as described above;

the piston is positioned at the inner side of the outer stator core, the rotor permanent magnet is connected with the piston and is relatively fixed, and the piston can linearly reciprocate in the cylinder sleeve under the drive of the rotor permanent magnet.

Optionally, the rotor permanent magnet is annular structure, be provided with the support frame on the piston, the rotor permanent magnet sets up on the support frame, and be located between the cylinder jacket with outer stator core.

Optionally, the mover permanent magnet is of an annular structure, and the mover permanent magnet is sleeved on the outer side wall of the piston;

the cylinder sleeve is positioned at one side of the rotor permanent magnet in the axial direction.

Optionally, the mover permanent magnet is of an annular structure, an annular accommodating groove is formed in the outer side wall of the piston in an annular mode, and the mover permanent magnet is located in the annular accommodating groove.

Optionally, the outer peripheral surface of the mover permanent magnet does not protrude from the notch of the annular accommodating groove.

Optionally, the piston includes along the first column section and the second column section that the direction of movement of piston set gradually, first column section with the second column section divides to establish the both ends of rotor permanent magnet, and with the rotor permanent magnet is connected.

Optionally, the outer diameters of the first columnar section and the second columnar section are equal, the outer diameter of the mover permanent magnet is larger than the outer diameter of the first columnar section or the second columnar section, and the cylinder sleeve is positioned at one side of the mover permanent magnet in the axial direction;

or the outer diameter of the first columnar section, the outer diameter of the second columnar section and the outer diameter of the mover permanent magnet are equal.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

according to the linear motor and the linear compressor, the two groups of stator winding coils with opposite winding directions are wound on the outer stator iron core, so that the mover permanent magnet is located on the inner side of the outer stator iron core, the mover permanent magnet is arranged to be an axially magnetized permanent magnet, meanwhile, the magnetizers are arranged at the two axial ends of the mover permanent magnet, when the stator winding coils are electrified, the two groups of coils can form an overlapped magnetic field in space, and the mover permanent magnet can linearly reciprocate under the electromagnetic force action of an alternating magnetic field through changing the direction of current. Meanwhile, as the two axial ends of the mover permanent magnet are respectively provided with the magnetizer, the magnetizer has a magnetic conduction effect, so that the magnetic resistance in a magnetic circuit can be reduced, the magnetic circuit efficiency is improved, the electromagnetic thrust to the mover permanent magnet is increased, that is, the motor structure is more compact and the efficiency of the motor is improved; and because of the existence of the magnetizer, the situation that the two ends of the mover permanent magnet are damaged due to collision in the installation or use process can be avoided, and meanwhile, when the motor fails, the situation that the permanent magnet is demagnetized due to magnetomotive force generated by motor current can be avoided, so that the effect of protecting the mover permanent magnet is achieved, and the service life of the motor is prolonged. In addition, the outer diameter of the magnetizer is not smaller than that of the mover permanent magnet, so that the guiding effect of the magnetizer on magnetic force lines can be further improved, the magnetic conduction effect is improved, the eddy current loss of a magnetic field is reduced, and better protection of the mover permanent magnet can be realized.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments of the present disclosure or the solutions in the prior art, the drawings that are required for the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.

FIG. 1 is a partial sectional view of a linear compressor according to an embodiment of the present disclosure;

FIG. 2 is a partial structural cross-sectional view of a linear motor according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a linear motor according to an embodiment of the disclosure;

fig. 4 is a schematic diagram of a linear motor according to an embodiment of the disclosure;

FIG. 5 is a partial sectional view of a linear compressor according to an embodiment of the present disclosure;

FIG. 6 is a partial sectional view of a linear compressor according to an embodiment of the present disclosure;

FIG. 7 is a partial sectional view of a linear compressor according to an embodiment of the present disclosure;

FIG. 8 is a partial sectional view of a linear compressor according to an embodiment of the present disclosure;

fig. 9 is a partial structural sectional view six of a linear compressor according to an embodiment of the present disclosure.

Wherein, 1, a linear motor; 11. an outer stator core; 12. a stator winding coil; 13. a mover permanent magnet; 14. a magnetizer; 15. pole shoes; 2. a linear compressor; 21. a cylinder liner; 22. a piston; 220. an annular accommodating groove; 221. a first cylindrical section; 222. a second cylindrical section; 23. and (5) supporting frames.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, a further description of aspects of the present disclosure will be provided below. It should be noted that, without conflict, the embodiments of the present disclosure and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced otherwise than as described herein; it will be apparent that the embodiments in the specification are only some, but not all, embodiments of the disclosure.

The motor is a transmission device capable of converting electric energy into mechanical motion, and can be applied to a linear compressor, for example, and the linear motor drives a piston of the linear compressor to reciprocate so as to compress working media.

The linear motor of the prior art specifically includes: mover permanent magnet, outer stator core and the inside stator core that is located outside the outer stator core. The rotor permanent magnet is a radial magnetizing permanent magnet, the rotor permanent magnet is positioned between the outer stator core and the inner stator core, an alternating magnetic field can be generated when the winding coil wound on the outer stator core is electrified, and the rotor permanent magnet drives the piston of the compressor to linearly reciprocate under the magnetic force of the alternating magnetic field. However, the structure of the motor of the prior art is not compact enough, resulting in a large occupied space of the motor and thus a large volume of the linear compressor using the same.

Based on this, this embodiment provides a linear motor without an inner stator core and a linear compressor including the same, so as to improve the compactness of the motor structure and reduce the occupation space of the motor to a certain extent.

Example 1

Referring to fig. 1 to 8, the present embodiment provides a linear motor 1 including: mover permanent magnet 13, outer stator core 11, and stator winding coil 12 wound around outer stator core 11.

It is understood that the outer stator core is in particular annular. The outer stator core 11 and the stator winding coil 12 are formed as a stator part of the motor, and the mover permanent magnet 13 is formed as a mover part of the motor.

The stator winding coils 12 are two groups, the two groups of stator winding coils 12 are arranged on the outer stator core 11 at intervals, and the winding directions of the two groups of stator winding coils 12 are opposite. After the stator winding coils 12 are electrified, magnetic fields formed by the two groups of stator winding coils 12 can be overlapped and cannot be mutually counteracted, and the directions of magnetic lines of force at two sides of the outer stator core 11 are consistent.

The mover permanent magnet 13 is disposed inside the outer stator core 11. The mover permanent magnet 13 is an axial magnetizing permanent magnet, and the mover permanent magnet 13 can linearly reciprocate along the axial direction of the outer stator core 11 under the magnetic force generated by energizing the stator winding coil 12.

The stator winding coil 12 is electrified to generate an alternating magnetic field, and the mover permanent magnet 13 moves under the action of the alternating magnetic field of the space where the mover permanent magnet 13 is located, that is, electromagnetic force generates thrust to the mover permanent magnet 13, so that the linear reciprocating movement of the mover permanent magnet 13 is realized.

The material of the mover permanent magnet 13 may be a rare earth permanent magnet material, such as an iron rubidium boron permanent magnet material, and in this embodiment, the material of the mover permanent magnet 13 is not particularly limited, as long as it can do linear reciprocating movement under the magnetic force generated by energizing the stator winding coil 12 and drive other moving parts to move.

Illustratively, referring to fig. 3 and 4, the mover permanent magnet 13 has an N pole at the left end and an S pole at the right end. When a certain direction of current is applied to the stator winding coils 12, it can be approximately considered that the outer stator core 11 forms a magnetic pole as shown in fig. 3, and the winding directions of the two groups of stator winding coils 12 are opposite, at this time, the left side of the left stator winding coil 12 is an S pole, the right side is an N pole, the left side of the right stator winding coil 12 is an N pole, and the right side is an S pole. Since the same poles repel each other and the opposite poles attract each other, the mover permanent magnet 13 moves leftward by the attraction force of the left side.

Referring to fig. 4, when the direction of the current flowing into the stator winding coil 12 is changed, the outer stator core 11 forms a magnetic pole as in fig. 4, and the left side of the stator winding coil 12 is an N pole, the right side is an S pole, the left side of the stator winding coil 12 is an S pole, and the right side is an N pole. The magnetic pole direction of the mover permanent magnet 13 is unchanged, the left end of the mover permanent magnet 13 is an N pole, the right end is an S pole, and the mover permanent magnet 13 moves to the right side by the attraction of the right side due to the repulsion of homopolar and the attraction of heteropolar, so that the left-right reciprocating oscillation motion of the motor is realized under the condition of alternating current.

The above-mentioned mover permanent magnet 13 is axially magnetized, which is understood to mean that the magnetizing direction of the mover permanent magnet 13 is coaxial with the axial direction of the outer stator core 11 along the axial direction of the mover permanent magnet 13, that is, the magnetizing direction of the mover permanent magnet 13 is consistent with the moving direction of the mover permanent magnet 13 under the action of electromagnetic force.

Wherein, the two axial ends of the mover permanent magnet 13 are respectively provided with a magnetizer 14, and it can be understood that the magnetizer 14 has a magnetic conduction effect. The magnetic conductor 14 may be, for example, a soft magnetic material. The magnetic force lines can be guided by the magnetizers 14 positioned at the two ends of the mover permanent magnet 13 from the two ends of the mover permanent magnet, so that the magnetic force lines are concentrated on the mover permanent magnet 13 as much as possible, thereby reducing the magnetic circuit reluctance and the magnetic field eddy current loss, improving the magnetic circuit efficiency, correspondingly increasing the electromagnetic thrust to the mover permanent magnet 13 and improving the motor efficiency.

In addition, the mover of the linear motor 1 is designed to have a non-salient pole structure by providing the magnetizer 14. When the mover permanent magnet works, the mover permanent magnet is in a magnetizing and demagnetizing state, if the motor fails, magnetomotive force generated by motor current can lead the permanent magnet to be demagnetized irreversibly, and after the hidden pole structure is adopted, when the current is overlarge, the iron core can reach saturation, so that the mover permanent magnet 13 is protected.

Referring to fig. 1, 5 to 8, when the linear motor 1 is applied to the linear compressor 2, the linear motor 1 is disposed in a housing of the linear compressor 2, in which a piston and a cylinder liner are disposed. The piston 22 is positioned at the inner side of the outer stator core 11, the rotor permanent magnet 13 is connected with the piston 22 and is relatively fixed, and the piston 22 can linearly reciprocate in the cylinder sleeve 21 under the drive of the rotor permanent magnet 13. That is, the mover permanent magnet 13 makes a linear reciprocating motion under the alternating magnetic field generated by the energization of the stator winding coil 12, thereby driving the piston 22 to make a linear reciprocating motion in the cylinder liner 21. Referring to fig. 3 and 4, the mover permanent magnet 13 reciprocates left and right, thereby driving the piston 22 to reciprocate left and right.

Referring to fig. 2 to 8, the outer diameter of the magnetizer 14 can be made not smaller than the outer diameter of the mover permanent magnet 13, so that the guiding effect of the magnetizer 14 on magnetic lines of force can be further improved, the magnetic conduction effect can be improved, the eddy current loss of the magnetic field can be reduced, and better protection of the mover permanent magnet 13 can be realized.

It should be noted that, the linear motor 1 provided in this embodiment may be applied to not only the linear compressor 2, such as a stirling compressor, but also other devices that need linear driving, and in particular, the mover permanent magnet 13 is connected to a moving member in the devices.

According to the linear motor 1 provided by the embodiment, two groups of stator winding coils 12 with opposite winding directions are wound on the outer stator core 11, the mover permanent magnet 13 is positioned on the inner side of the outer stator core 11, the mover permanent magnet 13 is set to be an axial magnetizing permanent magnet, when the stator winding coils 12 are electrified, the two groups of coils can form a superimposed magnetic field in space, and the mover permanent magnet 13 can linearly reciprocate under the electromagnetic force action of an alternating magnetic field by changing the direction of current; namely, the motor provided by the embodiment is a linear motor without an inner stator core; meanwhile, as the two axial ends of the mover permanent magnet 13 are respectively provided with the magnetizer 14, the magnetizer 14 has magnetic conduction effect, thereby reducing the magnetic resistance and the magnetic field eddy current loss in the magnetic circuit, improving the magnetic circuit efficiency, increasing the electromagnetic thrust to the mover permanent magnet 13, that is, improving the efficiency of the motor while ensuring the motor structure to be more compact; and because of the existence of the magnetizer 14, the situation that the two ends of the mover permanent magnet 13 are damaged due to collision in the installation or use process can be avoided, and meanwhile, when the motor fails, the situation that the permanent magnet is demagnetized due to magnetomotive force generated by motor current can be avoided, so that the effect of protecting the mover permanent magnet 13 is achieved, and the service life of the motor is prolonged. In addition, the outer diameter of the magnetizer is not smaller than that of the mover permanent magnet, so that the guiding effect of the magnetizer on magnetic force lines can be further improved, the magnetic conduction effect is improved, the eddy current loss of a magnetic field is reduced, and better protection of the mover permanent magnet can be realized.

In some embodiments, at least one of the two magnetic conductors 14 at two ends of the mover permanent magnet 13 is an iron core ring disposed at an end of the mover permanent magnet 13. Referring to fig. 1, 5 and 6, the magnetizers 14 at both ends of the mover permanent magnet 13 are iron core rings.

Through setting up the magnetizer 14 into the iron core ring, can further improve magnetic conduction effect, and then further improve magnetic circuit efficiency, and then increased electromagnetic thrust, further reduce the magnetic field eddy current loss for the efficiency of motor is higher, can protect rotor permanent magnet 13 from the whole circumference at rotor permanent magnet 13 both ends in addition, has further improved rotor permanent magnet 13's life.

Of course, in other implementations, the magnetizer 14 may include, for example, a protecting member disposed at an end of the mover permanent magnet 13, and the protecting member is filled with magnetic powder, so that a magnetic permeability effect may be achieved, and the protecting member may be annular, or may be block-shaped or columnar.

In particular, when the magnetic conductor 14 is implemented, the magnetic conductor can be attached to the mover permanent magnet 13, so that the magnetic conducting effect can be further ensured, and meanwhile, the protection effect of the magnetic conductor on the mover permanent magnet 13 is further improved. For example, the magnetizer 14 is directly attached to the end of the mover permanent magnet 13.

In addition, the magnetizer 14 may be adhered to both ends of the mover permanent magnet 13 by an adhesive or the like so as to be integrally adhered to the mover permanent magnet 13, so that the assembly is convenient and the connection is reliable. Of course, the magnetizer 14 may be connected to the mover permanent magnet 13 by other fixing means.

In some embodiments, the position of the mover permanent magnet 13 in the axial direction is located between two sets of stator winding coils 12 when the stator winding coils 12 are not energized. As shown with reference to fig. 2 to 4, that is, when the stator winding coils 12 are not energized, the mover permanent magnet 13 is positioned corresponding to the position between the two sets of stator winding coils 12, so that the mover permanent magnet 13 moves leftward in a uniform magnitude with the rightward movement in a case where the applied magnetic force is equal, thereby improving the reciprocating oscillation effect of the motor.

With continued reference to fig. 2, in a specific implementation, the length a of the mover permanent magnet 13 in the axial direction may be made greater than the spacing distance b between the inner sides of the two sets of stator winding coils 12. The inner side here is the side where the two sets of stator winding coils 12 are close to each other. The arrangement can ensure the acting force of the alternating magnetic field generated by the winding coil on the mover permanent magnet 13, ensure the moving range of the mover permanent magnet 13, reduce the motor loss and improve the motor efficiency.

The manner of arrangement between the mover permanent magnet 13 and the piston 22 of the linear compressor will be described in detail with reference to the accompanying drawings:

referring to fig. 1, in a first possible implementation manner, the mover permanent magnet 13 is specifically in a ring structure, and a support 23 is provided on the piston 22, so that the mover permanent magnet 13 is fixed on the support 23, and when the mover permanent magnet 13 reciprocates under the action of electromagnetic force, the piston 22 is driven to reciprocate.

In this implementation, the cylinder liner 21 is specifically disposed inside the outer stator core 11, and the mover permanent magnet 13 is located between the cylinder liner 21 and the outer stator core 11.

The supporting frame 23 may be made of a lightweight material as long as effective supporting and fixing of the mover permanent magnet 13 can be satisfied. Specifically, the support 23 may be configured as an annular support, which is disposed around the periphery of the piston 22 and is fixed relative to the piston 22.

In this implementation, since the mover permanent magnet 13 is located at the outer side of the cylinder liner 21, the mover permanent magnet 13 is closer to the stator winding coil 12, so that the force of the mover permanent magnet 13 subjected to the magnetic field is stronger, and the motor efficiency is further improved.

Referring to fig. 5, in a second possible implementation, the mover permanent magnet 13 is specifically of an annular structure, and the mover permanent magnet 13 is sleeved on the outer side wall of the piston 22. That is, the mover permanent magnet 13 is sleeved on the piston 22, both of which are formed as one body. The magnetizer 14 is a magnetic conductive ring, and the outer diameter of the magnetizer 14 is equal to the outer diameter of the mover permanent magnet 13. In this implementation, the cylinder liner 21 is located specifically on one side in the axial direction of the mover permanent magnet 13.

In this implementation, since the mover permanent magnet 13 is directly sleeved on the piston 22 and the cylinder liner 21 is not located inside the outer stator core 11, the axial structure of the linear motor is more compact, and the volumes of the linear motor 1 and the linear compressor 2 are reduced to some extent.

Referring to fig. 6, in a third possible implementation manner, the mover permanent magnet 13 is specifically of an annular structure, an annular accommodating groove 220 that is annularly provided along the circumferential direction of the piston 22 is provided on the outer side wall of the piston 22, and the mover permanent magnet is located in the annular accommodating groove 220. The magnetizer 14 is a magnetic conductive ring, and the outer diameter of the magnetizer 14 is equal to the outer diameter of the mover permanent magnet 13. In such an implementation, the cylinder liner 21 may be located inside the outer stator core 11 in particular.

By arranging the annular accommodating groove 220 on the piston 22, the mover permanent magnet 13 is accommodated by the annular accommodating groove 220, so that the compactness of the upward structure of the linear motor shaft is further improved, and the volumes of the linear motor 1 and the linear compressor 2 are reduced to a certain extent.

Specifically, the outer peripheral surface of the mover permanent magnet 13 does not protrude from the notch of the annular accommodating groove 220, and with continued reference to fig. 6, the outer peripheral surface of the mover permanent magnet 13 and the outer peripheral surface of the magnetizer 14 are flush with the notch of the annular accommodating groove 220, so that the compactness of the axial structure is further improved.

Referring to fig. 7, in a fourth possible implementation, the mover permanent magnet 13 is a bar-shaped structure. The piston 22 specifically includes a first cylindrical section 221 and a second cylindrical section 222 that are sequentially disposed along the moving direction of the piston 22, and the first cylindrical section 221 and the second cylindrical section 222 are separately disposed at both ends of the mover permanent magnet 13 and connected to the mover permanent magnet 13.

In this implementation manner, the outer diameters of the first cylindrical section 221 and the second cylindrical section 222 are equal, and the outer diameter of the mover permanent magnet 13 is larger than the outer diameter of the first cylindrical section 221 or the second cylindrical section 222, wherein the magnetizer 14 has a bar-shaped structure or a block-shaped structure, and the outer diameter of the magnetizer 14 is equal to the outer diameter of the mover permanent magnet 13. The cylinder liner 21 is specifically located at one side in the axial direction of the mover permanent magnet 13.

In this implementation, since the mover permanent magnet 13 is connected between the first and second cylindrical sections 221 and 222, and the cylinder liner 21 is not located inside the outer stator core 11, the axial structure of the linear motor and the linear compressor is made more compact. Moreover, compared with the third implementation manner shown in fig. 6, in this solution, the distance between the mover permanent magnet 13 and the stator winding coil 12 is closer, so that the thrust of the magnetic field received by the mover permanent magnet 13 is further improved, and the efficiency of the motor is improved. In addition, compared with the second implementation manner shown in fig. 5, in this embodiment, the mover permanent magnet 13 is located between the first cylindrical section and the second cylindrical section, and is not annular, so that the acting force of the magnetic field applied to the mover permanent magnet 13 is greater, that is, the thrust applied to the mover permanent magnet 13 is greater, thereby improving the motor efficiency.

Referring to fig. 8, in a fifth possible implementation, the mover permanent magnet 13 is a bar-shaped structure. The piston 22 specifically includes a first cylindrical section 221 and a second cylindrical section 222 that are sequentially disposed along the moving direction of the piston 22, and the first cylindrical section 221 and the second cylindrical section 222 are separately disposed at both ends of the mover permanent magnet 13 and connected to the mover permanent magnet 13.

In this implementation, the outer diameter of the first cylindrical section 221, the outer diameter of the second cylindrical section 222, and the outer diameter of the mover permanent magnet 13 are equal. The magnetizer 14 has a bar-shaped structure or a block-shaped structure, and the outer diameter of the magnetizer 14 is equal to the outer diameter of the mover permanent magnet 13. The cylinder liner 21 is located specifically inside the outer stator core 11. Compared with the third implementation manner shown in fig. 6, since the mover permanent magnet 13 is located between the first cylindrical section and the second cylindrical section, and is not annular, the mover permanent magnet 13 receives a larger magnetic field force, that is, the mover permanent magnet 13 receives a larger thrust force, thereby improving the motor efficiency.

Further, as shown with reference to fig. 9, pole pieces 15 may be provided on the side of the outer stator core 11 close to the mover permanent magnet 13, specifically, the pole pieces 15 are located at both ends of the stator winding coil 12 in the axial direction. The pole shoes 15, i.e. the magnetic angle, are made of ferromagnetic material. That is, the pole piece 15 is located inside the outer stator core 11 and is disposed close to the mover permanent magnet 13. By providing the pole shoes 15, the thrust of the motor can be increased to a certain extent, so that the efficiency of the motor is higher.

For example, the pole piece 15 may be integrally formed with the outer stator core 11, i.e., the pole piece 15 is integrally formed thereon when the outer stator core 11 is manufactured. This arrangement can improve the overall structural strength to some extent.

Furthermore, the pole shoes 15 may also be a separate component mounted on the inner annular wall of the outer stator core 11.

It should be noted that the arrangement of the pole shoes 15 may be applied in any of the implementations shown in fig. 1 to 8.

The linear motor provided by the invention does not need an inner iron core, and has a simple and compact structure because the magnetizing direction is axial, and the weight and the volume are greatly improved compared with those of a common moving magnet motor, thereby having good development potential.

Example two

Referring to fig. 1, 5 to 9, the present embodiment provides a linear compressor 2 including: cylinder liner 21, piston 22, and linear motor 1.

The piston 22 is located at the inner side of the outer stator core 11, the mover permanent magnet 13 is connected with the piston 22 and is relatively fixed, and the piston 22 can linearly reciprocate in the cylinder sleeve 21 under the driving of the mover permanent magnet 13. That is, the moving direction of the mover permanent magnet 13 coincides with the moving direction of the piston 22.

The specific structure and implementation principle of the linear motor 1 in this embodiment are the same as those of the linear motor 1 provided in the foregoing embodiment, and the same or similar technical effects can be brought, which are not described in detail herein, and specific reference may be made to the description of the foregoing embodiment.

According to the linear compressor 2 provided by the embodiment, through winding two groups of stator winding coils 12 with opposite winding directions on the outer stator core 11 of the linear motor 1, the rotor permanent magnet 13 is positioned on the inner side of the outer stator core 11, the rotor permanent magnet 13 is set to be an axial magnetizing permanent magnet, when the stator winding coils 12 are electrified, an alternating magnetic field is formed in a space, and the rotor permanent magnet 13 can linearly reciprocate under the electromagnetic force action of the alternating magnetic field by changing the direction of current; meanwhile, as the two ends of the mover permanent magnet 13 are respectively provided with the magnetizer 14, the magnetizer 14 has magnetic conduction, thereby reducing the magnetic resistance and the magnetic field eddy current loss in the magnetic circuit, improving the magnetic circuit efficiency, and increasing the electromagnetic thrust to the mover permanent magnet 13, that is, the efficiency of the motor and the linear compressor is improved while the motor structure is more compact; and because of the existence of the magnetizer 14, the situation that the two ends of the mover permanent magnet 13 are damaged due to collision in the installation or use process can be avoided, and meanwhile, when the motor fails, the situation that the permanent magnet is demagnetized due to magnetomotive force generated by motor current can be avoided, so that the effect of protecting the mover permanent magnet 13 is achieved, and the service lives of the motor and the linear compressor are prolonged. In addition, the outer diameter of the magnetizer is not smaller than that of the mover permanent magnet, so that the guiding effect of the magnetizer on magnetic force lines can be further improved, the magnetic conduction effect is improved, the eddy current loss of a magnetic field is reduced, and better protection of the mover permanent magnet can be realized.

Other technical features are the same as those of the above embodiments, and can bring about the same or similar technical effects, and are not described in detail herein, and specific reference may be made to the descriptions of the above embodiments.

It should be noted that in this document, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely a specific embodiment of the disclosure to enable one skilled in the art to understand or practice the disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown and described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (14)

1. A linear motor, characterized by comprising a rotor permanent magnet (13), an outer stator core (11) and a stator winding coil (12) wound on the outer stator core (11);

the stator winding coils (12) are two groups, the two groups of stator winding coils (12) are arranged on the outer stator iron core (11) at intervals, and the winding directions of the two groups of stator winding coils (12) are opposite;

the rotor permanent magnet (13) is arranged on the inner side of the outer stator core (11); the rotor permanent magnet (13) is an axial magnetizing permanent magnet, two ends of the rotor permanent magnet (13) in the axial direction are respectively provided with a magnetizer (14), and the rotor permanent magnet (13) can linearly reciprocate along the axial direction of the outer stator core (11) under the action of magnetic force generated by energizing the stator winding coil (12);

wherein the outer diameter of the magnetizer (14) is not smaller than the outer diameter of the mover permanent magnet (13).

2. Linear motor according to claim 1, characterized in that at least one of the magnetic conductors (14) at both ends of the mover permanent magnet (13) is an iron core ring provided at an end of the mover permanent magnet (13).

3. A linear motor according to claim 1, characterized in that the magnetizer (14) is attached to the mover permanent magnet (13).

4. Linear motor according to claim 1, characterized in that the length of the mover permanent magnet (13) in the axial direction is larger than the distance between the inner sides of the two sets of stator winding coils (12).

5. Linear motor according to claim 1, characterized in that the mover permanent magnet (13) is positioned axially between two sets of stator winding coils (12) when the stator winding coils (12) are not energized.

6. Linear motor according to claim 1, characterized in that the side of the outer stator core (11) close to the mover permanent magnet (13) is provided with pole shoes (15), which pole shoes (15) are located at both ends of the stator winding coil (12) in the axial direction.

7. Linear motor according to claim 6, characterized in that the pole shoes (15) are integrally formed with the outer stator core (11).

8. A linear compressor comprising a cylinder liner (21), a piston (22) and a linear motor according to any of claims 1 to 7;

the piston (22) is located on the inner side of the outer stator core (11), the rotor permanent magnet (13) is connected with the piston (22) and is relatively fixed, and the piston (22) can linearly reciprocate in the cylinder sleeve (21) under the drive of the rotor permanent magnet (13).

9. Linear compressor according to claim 8, characterized in that the mover permanent magnet (13) is of annular structure, the piston (22) is provided with a support frame (23), the mover permanent magnet (13) is provided on the support frame (23) and between the cylinder liner (21) and the outer stator core (11).

10. Linear compressor according to claim 8, characterized in that the mover permanent magnet (13) is of annular structure, the mover permanent magnet (13) being sleeved on the outer side wall of the piston (22);

the cylinder sleeve (21) is positioned at one side of the rotor permanent magnet (13) in the axial direction.

11. Linear compressor according to claim 8, characterized in that the mover permanent magnet (13) is of annular structure, an annular accommodation groove (220) is provided on the outer side wall of the piston (22) and is annularly provided along the circumferential direction of the piston (22), and the mover permanent magnet (13) is located in the annular accommodation groove (220).

12. The linear compressor according to claim 11, wherein the outer peripheral surface of the mover permanent magnet (13) does not protrude from the notch of the annular receiving groove (220).

13. The linear compressor according to claim 8, wherein the piston (22) includes a first cylindrical section (221) and a second cylindrical section (222) which are sequentially provided along a moving direction of the piston (22), the first cylindrical section (221) and the second cylindrical section (222) being provided separately at both ends of the mover permanent magnet (13) and connected to the mover permanent magnet (13).

14. The linear compressor according to claim 13, wherein the first cylindrical section (221) and the second cylindrical section (222) have an equal outer diameter, the mover permanent magnet (13) has an outer diameter larger than that of the first cylindrical section (221) or the second cylindrical section (222), and the cylinder liner (21) is located at one side in the axial direction of the mover permanent magnet (13);

alternatively, the outer diameter of the first cylindrical section (221), the outer diameter of the second cylindrical section (222) and the outer diameter of the mover permanent magnet (13) are equal.