CN217282522U - Linear motor for Stirling refrigerator - Google Patents

Abstract

The application relates to the technical field of refrigeration equipment, and discloses a linear motor for a Stirling refrigerator, which comprises: casing, active cell and shock-absorbing structure. In this application, can be through setting up shock-absorbing structure in the casing, under the condition of the vibration signal reinforcing of active cell, the snubber block of being connected with electro-magnet magnetism absorption can drop on braced frame, changes braced frame's weight, makes braced frame's the skew actual vibration frequency of vibration frequency to reduce the resonance that active cell and linear electric motor wholly produced, improve linear electric motor's work efficiency, extension linear electric motor's life.

Description

Linear motor for Stirling refrigerator

Technical Field

The application relates to the technical field of refrigeration equipment, in particular to a linear motor for a Stirling refrigerator.

Background

The Stirling refrigerating machine has the characteristics of large refrigerating capacity and long service life, the requirements on various aspects are continuously improved along with the wide application of the Stirling refrigerating machine in various fields, and the working principle shows that the vibration of the refrigerating machine is mainly generated by the motion of the linear motor, so that the vibration reduction of the linear motor is very important.

There is a moving-magnet linear motor among the correlation technique, including casing and active cell, the active cell includes piston, permanent magnet support and leaf spring, and the permanent magnet support is cylindric structure, permanent magnet support bottom with piston tip fixed connection together through the connecting bolt that is equipped with leaf spring's center department fixed connection, the terminal surface that leaf spring is close to the periphery department pass through tubular structure the motor mounting with outer yoke iron fixed connection, the both ends of motor mounting be equipped with respectively with leaf spring with the connecting portion of outer yoke iron looks adaptation carry out radial ascending support through leaf spring to piston and permanent magnet support, reduce the vibration that piston and permanent magnet support produced in the motion process.

In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

the vibration generated by the rotor during movement can cause the resonance of the whole linear motor, and the resonance can cause the friction between the rotor and the cylinder, thereby affecting the working efficiency of the linear motor and reducing the service life of the linear motor.

SUMMERY OF THE UTILITY MODEL

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.

The embodiment of the disclosure provides a linear motor for a Stirling refrigerator, which reduces vibration generated by a rotor, reduces resonance of the rotor and the linear motor as a whole, and prolongs the service life of the linear motor.

In some embodiments, a linear motor for a stirling cooler, comprising: casing, active cell and shock-absorbing structure. A cylinder is arranged in the shell; the rotor comprises a piston, a supporting frame and a permanent magnet arranged on the supporting frame, the piston is movably arranged in the cylinder, one axial end of the piston is connected with the supporting frame, and the supporting frame is sleeved on the outer wall of the cylinder; the damping structure comprises an electromagnet, a sensor and a damping block, the electromagnet is fixedly arranged on the inner wall of the upper side of the shell corresponding to the supporting frame, the damping block is in magnetic adsorption connection with the electromagnet, and the sensor is arranged on the inner wall of the shell and is electrically connected with the electromagnet; the sensor can sense a vibration signal generated by the permanent magnet, the vibration signal is converted into a voltage form to act on the electromagnet, the voltage acting on the electromagnet is inversely proportional to the strength of the vibration signal, and the magnetic adsorption strength of the electromagnet changes along with the change of the vibration signal, so that the damping block can be separated from the adsorption of the electromagnet and fall on the supporting frame.

In the embodiment of the disclosure, the permanent magnet on the supporting frame is repeatedly acted by the magnetic force under the change of the alternating magnetic field, so that the supporting frame drives the piston connected with the supporting frame to do telescopic motion repeatedly, the gas in the compression cylinder does work, the supporting frame and the piston can vibrate in the motion process, thereby causing the supporting frame and the linear motor to generate resonance integrally, the sensor can sense the vibration signal generated by the supporting frame and convert the vibration signal into a voltage form to act on the electromagnet, because the voltage acting on the electromagnet is inversely proportional to the strength of the vibration signal, under the condition that the vibration signal sensed by the sensor is enhanced, the voltage acting on the electromagnet is reduced, the voltage reduction can cause the magnetic adsorption strength of the electromagnet to be reduced, thereby causing the damping block magnetically adsorbed and connected with the electromagnet to drop on the supporting frame, and changing the weight of the supporting frame, the vibration frequency of the support frame is deviated from the actual vibration frequency, thereby reducing resonance generated by the support frame and the linear motor as a whole.

In some embodiments, the support frame upper side wall is provided with a groove corresponding to the position of the damper block, so that the dropped damper block can fall into the groove.

In some embodiments, the width of the groove is greater than the width of the damper block and less than or equal to three times the width of the damper block in the axial direction of the piston.

In some embodiments, the linear motor for a stirling cooler further comprises: a primary leaf spring. The first-level plate spring is connected with one axial end of the piston, and the outer ring of the first-level plate spring is fixed on the inner wall of the shell to radially support the piston.

In some embodiments, the primary leaf spring is disposed coaxially with both the piston and the support frame.

In some embodiments, the linear motor for a stirling cooler further comprises: a secondary leaf spring. The secondary plate spring is arranged on one side of the primary plate spring, and a balancing weight is fixedly arranged on one side wall of the secondary plate spring, which is back to the primary plate spring.

In some embodiments, the support frame is provided with a mounting groove, and the permanent magnet is embedded in the mounting groove.

In some embodiments, the linear motor for a stirling cooler further comprises: an outer stator and an inner stator. The outer stator is fixedly arranged on the inner wall of the shell; the inner stator is fixedly arranged on the outer wall of the cylinder and is positioned between the supporting frame and the outer wall of the cylinder.

In some embodiments, there is a gap between the support frame and the inner stator.

In some embodiments, the width of the gap is greater than or equal to 0.1 μm and less than 0.2 μm.

The linear motor for the Stirling refrigerator provided by the embodiment of the disclosure can realize the following technical effects:

through set up shock-absorbing structure in the casing, under the condition of the vibration signal reinforcing of active cell, the snubber block of being connected with electromagnet magnetism adsorption can drop on braced frame, changes braced frame's weight, makes braced frame's vibration frequency skew actual vibration frequency to reduce the resonance that active cell and linear electric motor wholly produced, improve linear electric motor's work efficiency, extension linear electric motor's life.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:

FIG. 1 is a schematic diagram of a linear motor for a Stirling cooler according to an embodiment of the present disclosure;

FIG. 2 is an enlarged schematic view of section A of FIG. 1 in accordance with an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of another linear motor for a Stirling cooler according to an embodiment of the present disclosure;

FIG. 4 is an exploded schematic view of a piston, support frame, primary plate spring, and armature provided by an embodiment of the present disclosure;

fig. 5 is a schematic view of a mounting structure of a permanent magnet provided by an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of another linear motor for a stirling cooler provided in an embodiment of the present disclosure.

Reference numerals are as follows:

100. a housing; 110. a cylinder; 120. an outer stator; 130. an inner stator;

200. a mover; 210. a piston; 211. connecting holes; 220. a support frame; 221. a groove; 222. a frame body through hole; 223. mounting grooves; 230. a permanent magnet;

300. a shock-absorbing structure; 310. an electromagnet; 320. a sensor; 330. a damper block;

400. a primary leaf spring; 410. a threaded hole; 420. an armature; 430. locking the nut;

500. a secondary leaf spring; 510. a counterweight block; 520. a jack; 530. and (7) connecting pins.

Detailed Description

So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.

The terms "first," "second," and the like in the description and in the claims, and the above-described drawings of embodiments of the present disclosure, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the present disclosure described herein may be made. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.

In the embodiments of the present disclosure, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the disclosed embodiments and their examples and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation. Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the embodiments of the present disclosure can be understood by those of ordinary skill in the art as appropriate.

In addition, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. Specific meanings of the above terms in the embodiments of the present disclosure can be understood by those of ordinary skill in the art according to specific situations.

The term "plurality" means two or more unless otherwise specified.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

The Stirling refrigerator absorbs heat by virtue of gas expansion in the discharger, and the refrigerating temperature of the Stirling refrigerator can be as low as minus two hundred and seventy degrees centigrade. The Stirling refrigerator has the advantages of compact structure, wide working temperature range, quick start, high efficiency, simple and convenient operation and the like. The working principle of Stirling is that the volume of working gas in an initial state is compressed by a compressor driven by a linear motor, the temperature of the working gas is increased while the gas is compressed, the temperature of the working gas is reduced by a heat regenerator, the volume of the working gas is expanded in an ejector to absorb heat, and the working gas is circulated in a reciprocating manner, so that the temperature of one end of the ejector is continuously reduced, and the refrigerating function is realized. According to the working principle, the vibration of the Stirling refrigerator is mainly generated by the motion of the linear motor, so that the vibration reduction of the linear motor is important. The linear motor of the Stirling refrigerator can be divided into two main structural forms of a moving coil type and a moving magnet type. The moving-coil linear motor has no lateral magnetic pull force and no axial force during no-load, but has the defects of direct contact between the coil and a refrigeration working medium, pollution to the refrigeration working medium, short service life and the like. The moving magnet type linear motor is long in service life and high in reliability, but the moving magnet type linear motor has unilateral magnetic pull force, so that a rotor is easy to deflect to the side face, a piston excessively rubs against a cylinder, and a refrigerator is damaged. In order to reduce the effective air gap of the motor and improve the specific thrust of the linear motor, a stator core is adopted to have a tooth groove structure, but the lateral magnetic tension is large, and the structure has high requirement on the radial rigidity of a plate spring and often needs to be supported by double plate springs. The cogging configuration of the stator core reduces lateral magnetic pull forces, but has the adverse effect of increased leakage flux, and thus, improvements in linear motors are still needed.

As shown in fig. 1 to 6, an embodiment of the present disclosure provides a linear motor for a stirling cooler, including: a case 100, a mover 200, and a shock-absorbing structure 300. A cylinder 110 is arranged in the shell 100; the mover 200 includes a piston 210, a support frame 220, and a permanent magnet 230 disposed on the support frame 220, the piston 210 is movably disposed in the cylinder 110, one axial end of the piston 210 is connected to the support frame 220, and the support frame 220 is sleeved on an outer wall of the cylinder 110; the shock absorption structure 300 comprises an electromagnet 310, a sensor 320 and a shock absorption block 330, wherein the electromagnet 310 is fixedly arranged on the inner wall of the upper side of the shell 100 corresponding to the supporting frame 220, the shock absorption block 330 is in magnetic adsorption connection with the electromagnet 310, and the sensor 320 is arranged on the inner wall of the shell 100 and is electrically connected with the electromagnet 310; the sensor 320 can sense a vibration signal generated by the permanent magnet 230 and convert the vibration signal into a voltage to be applied to the electromagnet 310, the voltage applied to the electromagnet 310 is inversely proportional to the strength of the vibration signal, and the magnetic adsorption strength of the electromagnet 310 changes with the change of the vibration signal, so that the damper 330 can be detached from the adsorption of the electromagnet 310 and fall on the support frame 220.

In the embodiment of the present disclosure, the permanent magnet 230 on the supporting frame 220 is repeatedly acted by the magnetic force under the change of the alternating magnetic field, so that the supporting frame 220 drives the piston 210 connected thereto to repeatedly make telescopic motion, the gas in the compression cylinder 110 does work, the supporting frame 220 and the piston 210 vibrate during the motion process, thereby causing the supporting frame 220 and the linear motor to resonate as a whole, the sensor 320 can sense the vibration signal generated by the supporting frame 220 and convert the vibration signal into a voltage form to act on the electromagnet 310, because the voltage acting on the electromagnet 310 is inversely proportional to the strength of the vibration signal, under the condition that the vibration signal sensed by the sensor 320 is enhanced, the voltage acting on the electromagnet 310 is reduced, the voltage reduction can cause the magnetic adsorption strength of the electromagnet 310 to be reduced, thereby causing the damper 330 magnetically adsorbed and connected to the electromagnet 310 to fall on the supporting frame 220, the weight of the support frame 220 is changed to deviate the vibration frequency of the support frame 220 from the actual vibration frequency, thereby reducing the resonance generated by the support frame 220 and the linear motor as a whole.

By adopting the linear motor for the stirling cryocooler provided by the embodiment of the present disclosure, the damping structure 300 is arranged in the housing 100, and under the condition that the vibration signal of the mover 200 is enhanced, the damping block 330 magnetically attached to the electromagnet 310 drops on the supporting frame 220, and the weight of the supporting frame 220 is changed, so that the vibration frequency of the supporting frame 220 deviates from the actual vibration frequency, thereby reducing the resonance generated by the mover 200 and the linear motor as a whole, improving the working efficiency of the linear motor, and prolonging the service life of the linear motor.

Optionally, the sensor 320 is a piezoelectric vibration sensor 320. Thus, the piezoelectric vibration sensor 320 converts the vibration signal into an electrical signal, and controls the voltage applied to the electromagnet 310 to change in the opposite direction according to the change in the electrical signal output from the piezoelectric vibration sensor 320, thereby controlling the magnetic attraction strength of the electromagnet 310.

As shown in fig. 2, in some embodiments, the support frame 220 is provided with a groove 221 on the upper sidewall thereof corresponding to the position of the damper block 330, so that the dropped damper block 330 can fall into the groove 221. Thus, as the vibration signal of the supporting frame 220 is enhanced, the voltage acting on the electromagnet 310 is reduced, so that the magnetic adsorption strength of the electromagnet 310 is reduced, and the damper 330 magnetically adsorbed and connected with the electromagnet 310 is separated from the adsorption of the electromagnet 310 and falls off, because the supporting frame 220 is a part of the mover 200, the supporting frame 220 drives the piston 210 to perform telescopic motion during operation, so that the damper 330 falling on the supporting frame 220 is flushed out along with inertia, and the damping effect of the damper 330 is affected, therefore, the groove 221 is arranged on the upper side wall of the supporting frame 220 corresponding to the damper 330, when the damper 330 falls off, the groove 221 can play a role of holding the damper 330, so that the falling damper 330 falls into the groove 221, the damper 330 is limited by the groove 221, the damper 330 is prevented from being separated from the supporting frame 220 under the inertia effect, and the stability of the damper 330 is improved, under the action of the damping block 330, the vibration frequency of the support frame 220 deviates from the actual vibration frequency, so that the resonance generated by the mover 200 and the linear motor as a whole is reduced, the working efficiency of the linear motor is improved, and the service life of the linear motor is prolonged.

Alternatively, the damper block 330 is made of a magnetic metal alloy, for example, iron-nickel alloy. Thus, the shock absorbing block 330 made of iron-nickel alloy has strong magnetic adsorption and can be more stably adsorbed and connected with the electromagnet 310, and the shock absorbing block 330 made of iron-nickel alloy has good environmental adaptability and can reduce the influence caused by environmental change.

Alternatively, the supporting frame 220 has a cylindrical structure, and the groove 221 has an arc-shaped groove structure opened in the upper peripheral wall of the supporting frame 220. In this way, the support frame 220 with a cylindrical structure can be adapted to the installation of the cylinder 110, and better drives the piston 210 arranged in the cylinder 110 to do axial telescopic movement.

Alternatively, the width of the groove 221 is greater than the width of the damper block 330 and less than or equal to three times the width of the damper block 330 in the axial direction of the piston 210. Thus, when the linear motor works, the supporting frame 220 drives the piston 210 to perform an axial telescopic motion, so that the width of the groove 221 in the axial direction of the piston 210 is set to be greater than the width of the damper 330 and less than or equal to three times the width of the damper 330, so that the dropped damper 330 can fall into the groove 221 more accurately, and the damper 330 is prevented from being separated from the supporting frame 220 under the action of inertia.

Optionally, the width of the groove 221 is twice the width of the damper block 330. Therefore, the damping block 330 can fall into the groove 221 more accurately, the occupied area of the groove 221 on the upper peripheral wall of the supporting frame 220 can be reduced, and the influence of the overlarge occupied area of the groove 221 on the strength of the supporting frame 220 is avoided.

Alternatively, the distance from the lower end surface of the electromagnet 310 to the upper side peripheral wall of the support frame 220 in the radial direction of the support frame 220 is equal to the thickness of the damper 330. Thus, since the groove 221 is disposed inside the circumferential wall of the upper side of the supporting frame 220, when the damper 330 falls into the groove 221, the distance between the upper end surface of the damper 330 and the lower end surface of the electromagnet 310 is the depth of the groove 221, thereby preventing the damper 330 from contacting the electromagnet 310 and affecting the movement of the supporting frame 220, and when the vibration of the supporting frame 220 is weakened, the vibration signal sensed by the sensor 320 is small, so that the voltage applied to the electromagnet 310 is increased, the magnetism of the electromagnet 310 is restored, and under the magnetic attraction effect of the electromagnet 310, the damper 330 can be attracted again by the electromagnet 310, so that the damper 330 is better reset.

As shown in fig. 3 and 4 in combination, in some embodiments, the linear motor for a stirling cooler further includes: a primary leaf spring 400. The primary plate spring 400 is coupled to one end of the piston 210 in the axial direction, and the outer race of the primary plate spring 400 is fixed to the inner wall of the housing 100 to radially support the piston 210. In this way, the first-stage plate spring 400 is used to support the piston 210 and the support frame 220 in the radial direction, and when the support frame 220 drives the piston 210 to perform the axial telescopic motion, the radial direction of the support frame 220 and the piston 210 can be limited, so that the friction between the piston 210 and the inner wall of the cylinder 110 in the motion process is reduced, and the radial vibration of the support frame 220 and the piston 210 is reduced.

The primary leaf spring 400 is a circular structure cut from a metal plate, has a high supporting rigidity in a radial direction, and can be stretched and deformed in an axial direction to generate a resilient force, and when the primary leaf spring 400 is mounted, a plane thereof is perpendicular to an axis of the piston 210, and an outer ring thereof is fixed to an inner wall of the housing 100. The piston 210 can perform reciprocating telescopic motion in the axial direction, and the piston 210 is supported in the radial direction, so that the friction between the piston 210 and the inner wall of the cylinder 110 in the motion process is reduced, and the service lives of the piston 210 and the cylinder 110 are prolonged.

In one particular embodiment, the primary leaf spring 400 is disposed coaxially with both the plunger 210 and the support frame 220. Thus, when the primary plate spring 400 is stretched and deformed along with the movement of the piston 210, the radial supporting force can uniformly act on the supporting frame 220 and the piston 210, and the supporting frame 220 and the piston 210 are more stably supported in the radial direction, so that the piston 210 is not easily deviated in the radial direction, and the friction between the piston 210 and the inner wall of the cylinder 110 during the movement is reduced.

Optionally, the center of the primary plate spring 400 has a threaded hole 410, the center of one end face in the axial direction of the piston 210 has a connection hole 211, the center of the support frame 220 has a frame through hole 222, one end face in the axial direction of the piston 210 is attached to the support frame 220 coaxially, the primary plate spring 400 is connected with one end in the axial direction of the piston 210 through an armature 420, the armature 420 sequentially passes through the threaded hole 410 and the frame through hole 222 to extend into the connection hole 211 to be fixedly connected with the piston 210, the armature 420 is a circular shaft with an external thread structure, the inner wall of the connection hole 211 of the piston 210 has an internal thread, the primary plate spring 400 is screwed on the periphery of the armature 420 through the threaded hole 410 in the center, and one end of the armature 420 extends into the connection hole 211 of the piston 210 to be fixedly connected with the piston 210 through a thread. Thus, the axial positions of the first-stage plate spring 400, the piston 210 and the support frame 220 are all fixedly connected through the armature 420, and the external thread structure on the periphery of the armature 420 is matched with the internal thread structure on the inner wall of the connecting hole 211 and the threaded hole 410 in the center of the first-stage plate spring 400, so that the connection stability of the first-stage plate spring 400, the support frame 220 and the piston 210 is higher, and the first-stage plate spring 400 is better used for radially supporting the piston 210 and the support frame 220.

Optionally, the end of the armature 420 protruding the primary plate spring 400 is provided with a lock nut 430, and the lock nut 430 is sleeved on the outer peripheral wall of the armature 420. In this way, since the outer peripheral wall of the armature 420 has the external thread, the first plate spring 400 can be retracted by the rotation of the retraction nut, the connection stability between the first plate spring 400, the support frame 220, and the plunger 210 is further improved, and the first plate spring 400 is prevented from being separated from the armature 420 and losing the support in the radial direction of the plunger 210.

Optionally, fixing holes are formed in the axial end face of the supporting frame 220, which is attached to the piston 210, the fixing plate penetrates through the fixing holes through a bolt structure and is fixed to the axial end face of the piston 210, the number of the fixing holes is two, and the two fixing holes are symmetrically distributed on the axial end face of the supporting frame 220 by using the axis of the supporting frame 220. In this way, the fixing pieces are arranged to improve the connection stability between the piston 210 and the supporting frame 220, so that the piston 210 and the supporting frame 220 are connected not only through the armature 420, but also further fixed in the radial direction through the two symmetrically distributed fixing pieces, and the radial offset of the piston 210 in the movement process is reduced.

In some embodiments, the linear motor for a stirling cooler further comprises: the secondary leaf spring 500. The secondary plate spring 500 is disposed on one side of the primary plate spring 400, and a weight block 510 is fixedly disposed on a side wall of the secondary plate spring 500 opposite to the primary plate spring 400. In this way, by arranging the secondary plate spring 500 in the housing 100 and connecting the weight block 510 to the side wall of the secondary plate spring 500, the overall mass of the linear motor can be increased, so that the overall vibration frequency of the linear motor can be reduced, the vibration of the linear motor can be further reduced, and the working efficiency of the linear motor can be improved.

Optionally, a socket 520 is provided on the weight 510, and a connecting pin 530 passes through the socket 520 to fix the weight 510 to the secondary plate spring 500. In this way, the weight block 510 is fixed to the side wall of the secondary plate spring 500 by the connection pin 530 penetrating through the insertion hole 520, and the stability of the weight block 510 is improved.

It can be understood that the second-stage plate spring 500 is also a circular structure formed by cutting a metal plate, the outer ring of the second-stage plate spring is also fixedly connected with the inner wall of the shell 100, the counterweight block 510 is a circular structure matched with the shape of the second-stage plate spring 500, the counterweight block 510 is coaxially connected with the second-stage plate spring 500, so that the connection between the second-stage plate spring 500 and the counterweight block 510 is more stable, and when the linear motor vibrates, the stress of the second-stage plate spring 500 and the counterweight block 510 is more uniform.

Referring to fig. 5, in some embodiments, the supporting frame 220 is provided with a mounting groove 223, and the permanent magnet 230 is inserted into the mounting groove 223. Thus, the mounting groove 223 is formed in the support frame 220, the permanent magnet 230 is embedded in the mounting groove 223, the occupied space of the permanent magnet 230 can be reduced, the size of the linear motor is reduced, the permanent magnet 230 is prevented from excessively protruding out of the support frame 220, the specific thrust is increased, and the efficiency of the linear motor is improved.

In some embodiments, as shown in fig. 6, the linear motor for a stirling cooler further includes: an outer stator 120 and an inner stator 130. The outer stator 120 is fixedly disposed on the inner wall of the casing 100; the inner stator 130 is fixedly disposed on an outer wall of the cylinder 110 and is positioned between the support frame 220 and the outer wall of the cylinder 110. Thus, the operation of the linear motor depends on the alternating magnetic field generated by the cooperation of the outer stator 120 and the inner stator 130, so that the permanent magnet 230 arranged between the outer stator 120 and the inner stator 130 performs reciprocating telescopic motion under the action of the alternating magnetic field, the outer stator 120 is arranged on the inner wall of the shell 100, the inner stator 130 is fixedly arranged on the outer wall of the cylinder 110, the alternating magnetic field generated between the outer stator 120 and the inner stator 130 acts on the permanent magnet 230 in the supporting frame 220, so that the permanent magnet 230 performs reciprocating telescopic motion, the supporting frame 220 is driven by the permanent magnet 230 to move, and the piston 210 in the cylinder 110 is driven to perform reciprocating telescopic motion to compress the gas in the cylinder 110 to do work.

In some embodiments, the outer stator 120 is an outer yoke of the linear motor, the inner stator 130 is an inner yoke of the linear motor, the outer stator 120 is made of a magnetic steel sheet, a coil is arranged in the outer stator, an alternating current is supplied to the inner stator to generate an alternating magnetic field, and the inner stator 130 is made of a silicon steel sheet. Thus, an alternating magnetic field is generated between the outer stator 120 and the inner stator 130 by supplying alternating current to the coil provided in the outer stator 120, the inner stator 130 is provided on the outer wall of the cylinder 110, the outer stator 120 is provided on the inner wall of the casing 100, and the support frame 220 having the permanent magnet 230 attached thereto is provided between the inner stator 130 and the outer stator 120, so that the support frame 220 performs reciprocating telescopic motion under the action of the alternating magnetic field, thereby driving the piston 210 to move in the cylinder 110.

Optionally, a gap is provided between the support frame 220 and the inner stator 130. Thus, the support frame 220 and the permanent magnet 230 mounted on the support frame 220 are prevented from generating friction with the inner stator 130, and the leakage flux is reduced, thereby improving the operating efficiency of the linear motor.

Optionally, the width of the gap is greater than or equal to 0.1 μm and less than 0.2 μm. Thus, the support frame 220 is difficult to assemble when the gap between the support frame 220 and the inner stator 130 is less than 0.1 μm, friction is easily generated between the support frame 220 and the inner stator 130 when the support frame 220 vibrates, and the linear motor is easily damaged, and the leakage flux is large when the gap between the support frame 220 and the inner stator 130 is greater than or equal to 0.2 μm, thereby affecting the efficiency of the linear motor, so that the gap between the support frame 220 and the inner stator 130 is controlled to be greater than or equal to 0.1 μm and less than 0.2 μm, thereby reducing the leakage flux and improving the working efficiency of the linear motor while ensuring that the support frame 220 and the permanent magnet 230 mounted on the support frame 220 do not generate friction with the inner stator 130.

In a specific embodiment, the width of the gap is equal to 0.1 μm. Thus, setting the gap between the support frame 220 and the inner stator 130 to 0.1 μm can further reduce the amount of leakage flux and improve the operating efficiency of the linear motor.

The above description and drawings sufficiently illustrate embodiments of the disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. The embodiments of the present disclosure are not limited to the structures that have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (10)

1. A linear motor for a stirling cooler, comprising:

a housing having a cylinder therein;

the rotor comprises a piston, a supporting frame and a permanent magnet arranged on the supporting frame, the piston is movably arranged in the cylinder, one axial end of the piston is connected with the supporting frame, and the supporting frame is sleeved on the outer wall of the cylinder;

the damping structure comprises an electromagnet, a sensor and a damping block, the electromagnet is fixedly arranged on the inner wall of the upper side of the shell corresponding to the supporting frame, the damping block is in magnetic adsorption connection with the electromagnet, and the sensor is arranged on the inner wall of the shell and is electrically connected with the electromagnet;

the sensor can sense a vibration signal generated by the permanent magnet, the vibration signal is converted into a voltage to act on the electromagnet, the voltage acting on the electromagnet is inversely proportional to the strength of the vibration signal, and the magnetic adsorption strength of the electromagnet changes along with the change of the vibration signal, so that the damping block can be separated from the adsorption of the electromagnet and fall on the supporting frame.

2. A linear motor for a Stirling cooler according to claim 1,

the side wall on the supporting frame is provided with a groove corresponding to the position of the shock absorption block, so that the dropped shock absorption block can fall into the groove.

3. A linear motor for a Stirling cooler according to claim 2,

in the axial direction of the piston, the width of the groove is larger than the width of the damper block and is smaller than or equal to three times of the width of the damper block.

4. A linear motor for a stirling cooler in accordance with claim 1, further comprising:

the primary plate spring is connected with one axial end of the piston, and the outer ring of the primary plate spring is fixed on the inner wall of the shell to radially support the piston.

5. A linear motor for a Stirling refrigerator according to claim 4, wherein the primary plate spring is disposed coaxially with both the piston and the support frame.

6. A linear motor for a Stirling cooler according to claim 4, further comprising:

and the secondary plate spring is arranged on one side of the primary plate spring, and a balancing weight is fixedly arranged on one side wall of the secondary plate spring, which is back to the primary plate spring.

7. A linear motor for a stirling cooler in accordance with claim 1, wherein the support frame is formed with a mounting groove, and the permanent magnet is fitted into the mounting groove.

8. A linear motor for a stirling cooler in accordance with any one of claims 1 to 7, further comprising:

the outer stator is fixedly arranged on the inner wall of the shell;

the inner stator is fixedly arranged on the outer wall of the cylinder and is positioned between the supporting frame and the outer wall of the cylinder.

9. A linear motor for a stirling cooler in accordance with claim 8, wherein a gap is provided between the support frame and the inner stator.

10. A linear motor for a Stirling cooler according to claim 9,

the width of the gap is greater than or equal to 0.1 μm and less than 0.2 μm.

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