CN215486435U

CN215486435U - Miniature moving-coil type linear vacuum pump

Info

Publication number: CN215486435U
Application number: CN202121689722.4U
Authority: CN
Inventors: 张成林
Original assignee: Jiangsu Zhenbo Intelligent Technology Co ltd
Current assignee: Jiangsu Zhenbo Intelligent Technology Co ltd
Priority date: 2020-11-24
Filing date: 2021-07-23
Publication date: 2022-01-11
Anticipated expiration: 2031-07-23

Abstract

The utility model discloses a miniature moving-coil type linear vacuum pump, and belongs to the technical field of vacuum pumps. The utility model discloses a miniature moving coil type linear vacuum pump which comprises a cavity, wherein a cavity vacuum control mechanism is connected to the cavity, a yoke and a moving coil are arranged in the cavity, a piston hole extending axially is formed in the middle of the yoke, a piston movably penetrates through the piston hole, an annular groove is formed in the yoke on the periphery of the piston hole, the inner wall of the annular groove is an inner yoke, the outer wall of the annular groove is an outer yoke, a magnet is arranged on the inner wall of the outer yoke, an annular space is formed between the inner yoke and the magnet, the piston is fixedly connected with the moving coil, the moving coil movably extends into the annular space, and the moving coil is controlled to reciprocate axially along the annular space by introducing alternating current to the moving coil. The micro moving-coil type linear vacuum pump has the advantages of compact structure, small volume, low noise, large flow, high efficiency and capability of realizing low vacuum.

Description

Miniature moving-coil type linear vacuum pump

Technical Field

The utility model belongs to the technical field of vacuum pumps, and particularly relates to a miniature moving-coil type linear vacuum pump.

Background

The vacuum fresh-keeping is used as a new generation of food storage technology, is comparable to zero-degree fresh-keeping, and can realize the effect of double fresh-keeping. The micro vacuum pump is particularly important as the core of the vacuum preservation technology. The micro vacuum pump has the characteristics of compact structure, low noise, low energy consumption, good stability, convenience for electric control and the like.

The vacuum pump is divided into a variable-volume vacuum pump and a momentum transfer vacuum pump. The variable-volume vacuum pump utilizes the periodic change of the volume of the pump cavity to realize air suction and air exhaust so as to achieve the purpose of vacuumizing. According to the driving principle, the variable-volume vacuum pump can be divided into a motor rotation driving impeller or piston type variable-volume vacuum pump, a piezoelectric material deformation driving diaphragm type variable-volume vacuum pump, an electromagnetic linear driving piston type variable-volume vacuum pump and the like. Currently, in the field of vacuum pumps, a variable-volume vacuum pump in the form of an impeller or a piston is driven mostly through a rotary motion structure, and a variable-volume vacuum pump in the form of a diaphragm is driven through deformation of a piezoelectric material.

The conventional vacuum pump is driven by a rotary motor, and the rotary power is converted into linear reciprocating motion through a transmission mechanism such as a crank connecting rod or an eccentric wheel mechanism, and then a piston is driven to reciprocate. It is not convenient for electronically controlled applications due to the following major drawbacks:

1) the whole machine has poor power performance and large noise. Since the crank-link mechanism converts the rotary motion of the motor into the reciprocating linear motion of the piston, the machine body is subjected to periodic reciprocating force and overturning moment, thereby causing large vibration and noise.

2) The mechanical efficiency is low. The electric motor converts the electric energy into the rotary mechanical energy, the rotary motion is converted into the reciprocating motion of the piston through the crank connecting rod mechanism, the energy transmission links are multiple, the cross sliding block and the piston are acted by lateral force to generate larger friction force, and the rotary friction power consumption is inevitably generated, so that the mechanical loss of the whole machine is larger, and the mechanical efficiency is low.

3) The volume is large. Because the rotating motor, the crank connecting rod mechanism, the piston and other transmission mechanisms are used, the whole structure occupies a larger space.

A variable-volume vacuum pump (hereinafter referred to as a piezoelectric diaphragm pump) in the form of a diaphragm driven by piezoelectric material deformation is often applied to a micro air pump. The piezoelectric material (such as PZT or ZnO) generates strain deformation after being electrified, and drives the diaphragm to reciprocate. This driving has the advantage of a fast reaction speed. The piezoelectric diaphragm pump directly or indirectly utilizes the mechanical deformation of the piezoelectric vibrator to change the volume of a pump cavity, and realizes the unidirectional flow of fluid through a one-way valve. The flow rate of the piezoelectric diaphragm pump is generally in the order of 1ml/min, so that the flow rate is too small, and the influence of the physical properties of the piezoelectric material is great.

The linear compressor is a novel refrigeration compressor driven by utilizing the principles of electromagnetism and mechanical vibration. At present, in the field of linear compressors, compressors of the electromagnetic linear driving piston type (hereinafter, referred to as electromagnetic linear driving type) are applied. The electromagnetic drive linear compressor directly drives the piston to reciprocate through the linear driving device, and has the advantages of compact structure, low noise, large flow, high efficiency and the like. According to the characteristics of the linear driving device, the electromagnetic driving linear compressor can be divided into three types: moving-coil type (Moving-coil), Moving-iron type (Moving-iron), and Moving-magnet type (Moving-magnet). At present, in the field of vacuum pumps, no moving-iron type or moving-magnetic type vacuum pump exists.

Disclosure of Invention

The utility model aims to provide a miniature moving-coil type linear vacuum pump which has the characteristics of compact structure, low noise, large flow, high efficiency and the like.

Specifically, the utility model provides a micro moving coil type linear vacuum pump, which comprises a cavity, wherein a cavity vacuum control mechanism is connected to the cavity, a yoke and a moving coil are arranged in the cavity, an axially extending piston hole is formed in the middle of the yoke, a piston movably penetrates through the piston hole, an annular groove is formed in the yoke on the periphery of the piston hole, the inner wall of the annular groove is an inner yoke, the outer wall of the annular groove is an outer yoke, a magnet is arranged on the inner wall of the outer yoke, an annular space is formed between the inner yoke and the magnet, the piston is fixedly connected with the moving coil, the moving coil movably extends into the annular space, and the moving coil is controlled to axially reciprocate along the annular space by introducing alternating current into the moving coil.

Furthermore, the miniature moving-coil type linear vacuum pump also comprises a moving coil movement buffer component connected with the moving coil.

Further, the moving coil movement buffering component is a spring, and the spring is connected between the moving coil and the inner yoke iron and/or the spring is connected between the moving coil and the cavity.

Further, an air inlet and an air outlet are arranged on the side wall of the cavity, the cavity vacuum control mechanism is a one-way valve, and the one-way valve is respectively arranged on the air inlet and the air outlet.

Further, the cavity vacuum control mechanism is arranged at the top of the cavity, and the piston hole is upwards communicated to the cavity vacuum control mechanism at the top; or the cavity vacuum control mechanism is arranged at the bottom of the cavity, a through hole which penetrates downwards to the bottom cavity vacuum control mechanism along the axial direction is arranged on the side wall of the bottom of the cavity, and the bottom end of the piston extends into the through hole and can reciprocate in the through hole along the axial direction.

Further, the piston is installed in the piston hole through a bearing.

Furthermore, a sealing end cover is arranged on the other side of the cavity, and a vacuumizing hole is formed in the sealing end cover, so that the inside and the outside of the cavity are communicated.

Further, the natural frequency of the mechanical system of the micro moving-coil linear vacuum pump is equal to the frequency of the alternating current.

Further, the natural frequency of the mechanical system of the micro moving-coil type linear vacuum pump is 50Hz or 60 Hz.

Furthermore, the mass of a moving part in a mechanical system of the miniature moving-coil type linear vacuum pump is 0.2Kg, the spring stiffness is 19739N/m, the diameter of a cylinder is 12mm, the piston stroke is 6-10mm, the air gap magnetic induction is 0.3-0.35T, the effective length of a coil winding is 659.73m, the equivalent inductance of the coil is 0.01H, and the resistance of the coil is 1224 omega.

The utility model has the following beneficial effects: the utility model relates to a micro moving-coil type linear vacuum pump,

1) the structure is simple, and power conversion mechanisms such as a crank connecting rod and the like are not needed;

2) the driving force of the piston is always consistent with the motion direction of the piston, so that the piston is not acted by lateral force;

3) because the transmission links are few, the friction is little, and the energy loss of a mechanical system is very small;

4) oil-free lubrication, labyrinth sealing, gas bearing support and the like are easy to realize;

5) the piston stroke is not limited by a mechanical structure, and the exhaust volume of the vacuum pump can be continuously adjusted through the input of the control system.

6) The natural frequency of the mechanical system of the vacuum pump is designed to be equal to the frequency of alternating current led into the coil winding, so that the micro moving-coil type linear vacuum pump is ensured to work at a resonance point, the working efficiency is further improved, and the noise is reduced.

Drawings

FIG. 1 is a schematic half-sectional view of example 1 of the present invention.

Fig. 2 is a schematic perspective view of embodiment 1 of the present invention.

Fig. 3 is a schematic half-sectional perspective view of embodiment 1 of the present invention.

Fig. 4 is a perspective view of the end cap of embodiment 1 of the present invention.

Fig. 5 is a perspective view of a yoke in embodiment 1 of the present invention.

Fig. 6 is a schematic perspective view of a yoke in half section according to embodiment 1 of the present invention.

FIG. 7 is a schematic half-sectional view of example 2 of the present invention.

Fig. 8 is a schematic perspective view of embodiment 2 of the present invention.

Fig. 9 is a schematic half-sectional perspective view of embodiment 2 of the present invention.

Reference numerals in the drawings: 1-shell, 2-yoke iron, 20-cylinder end, 21-inner yoke iron, 211-spring installation groove, 22-outer yoke iron, 23-annular groove, 24-piston hole, 3-moving coil, 4-magnet, 5-air inlet and outlet end cover, 50-end cover body, 51-air inlet, 52-air outlet, 6-piston, 7-bearing, 71-first bearing, 72-second bearing, 8-spring, 9-sealing end cover and 91-through hole.

Detailed Description

The present invention will be described in further detail with reference to the following examples and the accompanying drawings.

The utility model relates to a micro moving-coil type linear vacuum pump, which comprises a cavity, wherein a cavity vacuum control mechanism is connected to the cavity, and a yoke 2 and a moving coil 3 are arranged in the cavity. The middle part of the yoke 2 is provided with an axially extending piston hole 24, and a piston 6 is movably arranged in the piston hole 24 in a penetrating way. An annular groove 23 is formed in the yoke 2 on the periphery of the piston hole 24, the inner wall of the annular groove 23 is an inner yoke 21, and the outer wall of the annular groove 23 is an outer yoke 22. The magnet 4 is mounted on the inner wall of the outer yoke 22, and an annular space is formed between the inner yoke 21 and the magnet 4. The piston 6 is fixedly connected with the moving coil 3, the moving coil 3 can movably extend into an annular space formed between the inner yoke 21 and the magnet 4, and the moving coil 3 can be controlled to do axial reciprocating motion along the annular space by introducing alternating current into the moving coil 3.

Preferably, the micro moving-coil linear vacuum pump of the present invention may further include a moving-coil movement damping member, such as a spring 8, connected to the moving coil 3. The spring 8 may be connected between the moving coil 3 and the inner yoke 21, and the spring 8 may be connected between the moving coil 3 and the cavity.

The cavity vacuum control mechanism can adopt a one-way valve, the side wall of the cavity is provided with an air inlet 51 and an air outlet 52, and the one-way valve is respectively arranged on the air inlet 51 and the air outlet 52.

The chamber vacuum control mechanism may be disposed at the top of the chamber, with the piston bore 24 extending upwardly through to the chamber vacuum control mechanism at the top. The cavity vacuum control mechanism can also be arranged at the bottom of the cavity, a through hole 91 which penetrates downwards to the bottom cavity vacuum control mechanism along the axial direction is arranged on the side wall of the bottom of the cavity, and the bottom end of the piston 6 extends into the through hole 91 and can reciprocate along the axial direction in the through hole.

The piston 6 is mounted in the piston bore 24 by means of a bearing 7.

Example 1:

one embodiment of the present invention is a micro moving-coil linear vacuum pump.

As shown in fig. 1 to 3, the micro moving-coil linear vacuum pump includes a cavity between a housing 1 and an air inlet and outlet end cap 5 and a sealing end cap 9, and the cavity includes a yoke 2, a moving coil 3, a magnet 4, a piston 6, a bearing 7 and a spring 8.

The shell 1 is cylindrical, one end of the shell is provided with an air inlet and outlet end cover 5, and the air inlet and outlet end cover 5 comprises an end cover body 50, and an air inlet 51 and an air outlet 52 are arranged on the end cover body; the air inlet 51 and the air outlet 52 are used for fixedly mounting a one-way valve to realize the vacuum pumping function. Preferably, the shapes of the air inlet 51 and the air outlet 52 are through holes or stepped holes, etc., as shown in fig. 4. End cover 9 is installed to the other end of casing 1, forms an empty cavity in the casing 1, is provided with the evacuation hole on the end cover 9 for the cavity is inside to communicate with each other with the cavity outside, is used for to the inside evacuation of cavity after the equipment of the miniature moving coil type linear vacuum pump of this embodiment is accomplished, later seals this evacuation hole, makes the required vacuum degree of cavity inside satisfying vacuum pump work. One end of the yoke 2 is a cylindrical end 20, and the other end is divided into two concentric annular columns, namely an inner yoke 21 and an outer yoke 22, and an annular groove 23 is formed between the inner yoke 21 and the outer yoke 22. As shown in fig. 5 and 6, the piston hole 24 is provided at the center of the inner yoke 21, and the spring mounting groove 211 is provided at the center of the outer end surface. The piston hole 24 is used for installing the fixed bearing 7, and the spring installation groove 211 is used for placing the spring 8. As shown in fig. 1, the cylindrical end 20 of the yoke 2 is closely attached to the inner wall of the housing 1 on the inlet/outlet end cover side, and the outer side of the outer yoke 22 is closely attached to the cylindrical inner wall of the housing 1. As shown in fig. 1 and 6, the bearing 7 is fixed in the piston hole 24 of the inner yoke 21. The piston 6 is mounted in a piston hole 24 of the inner yoke 21 of the yoke 2 through a bearing 7, extends out of the inner yoke 21, and can reciprocate linearly in the axial direction of the bearing 7. The center section of the moving coil 3 is U-shaped, and the side portions of the U-shape are located between the inner yoke 21 and the outer yoke 22. The magnet 4 is fixed to the inner wall of the outer yoke 22, and an annular space is formed between the inner yoke 21 and the magnet 4. After the coil in the moving coil 3 is electrified, the yoke 2, the moving coil 3 and the magnet 4 form a closed magnetic field. When alternating current is introduced into the coil of the moving coil 3, an alternating magnetic field is formed, and the alternating magnetic field interacts with the magnetic field of the magnet 4 to drive the moving coil 3 to do linear reciprocating motion along the axial direction in an annular space formed by the inner yoke 21 and the magnet 4. The outer end of the piston 6 extending out of the inner yoke 21 is fixedly connected with the bottom (i.e. the bottom of the U-shape) of the moving coil 3. And a spring 8 is fixedly arranged on the outer side of the bottom of the moving coil 3 along the axial direction, one end of the spring 8 is abutted against the outer end part of the piston 6 extending out of the inner yoke 21, and the other end of the spring 8 is fixed on the inner side of the sealing end cover 9. When the moving coil 3 makes a linear reciprocating motion in the axial direction in the annular space formed by the inner yoke 21 and the magnet 4 under the electromagnetic force action of the alternating electromagnetic field, the piston 6 is driven to make a linear reciprocating motion in the axial direction of the bearing 7 according to the natural frequency of the alternating current. The linear maximum stroke of the spring 8 is smaller than the maximum stroke of the piston. In order to improve the working efficiency and reduce the noise, springs 8 can be arranged at the bottom of the moving coil 3 along the two sides of the axial direction. One end of a spring 8 provided inside the moving coil 3 is placed in the spring mounting groove 211 of the inner yoke 21, and the other end abuts against the inside of the bottom of the moving coil 3.

It will be appreciated that other yoke configurations may be used, for example, the inner yoke 21 and the outer yoke 22 may be of a unitary construction or may be secured together by two yokes.

Example 2:

another embodiment of the present invention is a micro moving-coil linear vacuum pump.

This embodiment is different from embodiment 1 in the positions of the piston and the intake/exhaust port. As shown in fig. 7 to 9, the micro moving-coil linear vacuum pump of the present embodiment includes a cavity formed between a housing 1 and an air inlet/outlet end cap 5 and a sealing end cap 9, and the cavity includes a yoke 2, a moving coil 3, a magnet 4, a piston 6, a first bearing 71, a second bearing 72, and a spring 8.

The casing 1 is cylindrical, one end is closed, and the other end is provided with an opening. One end of the sealing end cover 9 is an annular column, is inserted into the opening part of the shell 1, is attached to the inner wall of the shell 1 and is connected with the outer yoke 22. The other end of the end cap 9 is provided with a cylindrical through hole 91 communicating with the inside of the annular cylinder inserted into the housing 1. An air inlet end cover 5 is arranged outside the through hole 91, and an empty cavity is formed in the shell 1. The air inlet and outlet end cover 5 comprises an end cover body 50, an air inlet 51 and an air outlet 52 are arranged on the end cover body; the air inlet 51 and the air outlet 52 are used for fixedly mounting a one-way valve to realize the vacuum pumping function. Preferably, the shapes of the air inlet 51 and the air outlet 52 are through holes, stepped holes, or the like. One end of the yoke 2 is a cylindrical end 20, and the other end is divided into two concentric annular columns, namely an inner yoke 21 and an outer yoke 22, and an annular groove 23 is formed between the inner yoke 21 and the outer yoke 22. As shown in fig. 4 and 5, a piston hole 24 is formed in the center of the inner yoke 21, a spring mounting groove 211 is formed in the center of the outer end surface, the piston hole 24 is used for mounting the fixed bearing 7, and the annular groove is used for placing the spring 8. As shown in fig. 7, the cylindrical end 20 of the yoke 2 is closely attached to the inner wall of the casing 1 to which the inlet/outlet end caps are attached, and the outer side of the outer yoke 22 is closely attached to the cylindrical inner wall of the casing 1. The first bearing 71 is fixed in the piston hole 24 of the inner yoke 21, and the second bearing 72 is fixed in the through hole 91 of the end cover 9. The piston 6 is mounted in the piston hole 24 of the inner yoke 21 of the yoke 2 through a first bearing 71 and extends out of the inner yoke 21; the piston 6 is installed in the through hole 91 of the seal end cover 9 through the second bearing 72, and the piston 6 can linearly reciprocate along the axial direction of the first bearing 71 and the second bearing 72. The center section of the moving coil 3 is U-shaped, and the side portions of the U-shape are located between the inner yoke 21 and the outer yoke 22. The magnet 4 is fixed to the inner wall of the outer yoke 22, and an annular space is formed between the inner yoke 21 and the magnet 4. After the coil of the moving coil 3 is electrified, the yoke 2, the moving coil 3 and the magnet 4 form a closed magnetic field. When alternating current is introduced into the coil of the moving coil 3, an alternating magnetic field is formed, and the alternating magnetic field interacts with the magnetic field of the magnet 4 to drive the moving coil 3 to do linear reciprocating motion along the axial direction in an annular space formed by the inner yoke 21 and the magnet 4. The outer end of the piston 6 extending out of the inner yoke 21 is fixedly connected with the bottom (i.e. the bottom of the U-shape) of the moving coil 3. And a spring 8 is fixedly arranged on the outer side of the bottom of the moving coil 3 along the axial direction, one end of the spring 8 is abutted against the outer end part of the piston 6 extending out of the inner yoke 21, and the other end of the spring 8 is fixed on the inner side of the sealing end cover 9. When the moving coil 3 is reciprocated linearly in the axial direction in the annular space formed by the inner yoke 21 and the magnet 4 by the electromagnetic force of the alternating electromagnetic field, the piston 6 is driven to reciprocate linearly in the axial direction of the first bearing 71 and the second bearing 72 at the natural frequency of the alternating current. Wherein the linear maximum stroke of the spring 8 is smaller than the maximum stroke of the piston 6. In order to improve the working efficiency and reduce the noise, springs 8 can be arranged at the bottom of the moving coil 3 along the two sides of the axial direction. One end of a spring 8 provided inside the moving coil 3 is placed in the spring mounting groove 211 of the inner yoke 21, and the other end abuts against the inside of the bottom of the moving coil 3.

It will be appreciated that other yoke configurations may be used, for example, the inner yoke 21 and the outer yoke 22 may be of a unitary construction or, in another embodiment, may be secured together by two yokes.

Example 3:

in order to further improve the working efficiency and reduce the noise, in another embodiment, the mechanical system formed by the yoke 2, the moving coil 3, the piston 6, the bearing 7, the spring 8 and the sealing end cap 9 of the micro moving-coil type linear vacuum pump of embodiment 1 has a natural frequency f set to be equal to the natural frequency of the alternating current passing through the coil, so as to ensure that the linear vacuum pump system works at a resonance point. In order to effectively utilize energy and maximize the operating efficiency of the vacuum pump, the natural frequency of the mechanical system of the vacuum pump is generally designed to be about 50Hz or 60 Hz.

In another embodiment, the mechanical system formed by the yoke 2, the moving coil 3, the piston 6, the first bearing 71, the second bearing 72, the spring 8 and the end cap 9 of the micro moving-coil linear vacuum pump of embodiment 2, the natural frequency f of which is set to be equal to the natural frequency of the alternating current passing through the coil 3, ensures that the micro moving-coil linear vacuum pump system of the present invention operates at the resonance point to further improve the operating efficiency and reduce the noise. Preferably, in another embodiment, in order to effectively utilize energy and maximize the operation efficiency of the micro moving-coil linear vacuum pump, the natural frequency of the mechanical system of the micro moving-coil linear vacuum pump is designed to be about 50Hz or 60 Hz.

The reciprocating motion of the rotor (piston 6) of the miniature moving-coil linear vacuum pump is a complex nonlinear process related to dynamics, electromagnetics and thermodynamics. Therefore, the micro moving-coil type linear vacuum pump comprises three subsystems, namely a mechanical power system, a thermodynamic system and an electromagnetic system.

Wherein the content of the first and second substances,

m is the mass (unit: kg) of the moving part,

x is the spring displacement (unit: m),

t is the time (unit: s),

c is the damping coefficient of the magnetic field,

k is the spring rate (unit: N/m)

R is coil resistance (unit: omega)

i (t) is the current (unit: A)

u (t) is voltage (unit: V)

B_eFor air gap magnetic induction (unit: T)

L_eIs the effective length (unit: m) of the coil

L is coil equivalent inductance (unit: H)

F_m(t)＝B_eL_ei(t)，

P_oIs the pressure of the outlet air (unit: Pa)

x₀Is the initial displacement (unit: m) of the spring

According to the vacuum degree of 0.5 atmospheric pressure as input condition, and

the equation for the system is obtained as follows:

wherein:

n is the number of coil layers

By analyzing the formula, the natural frequency of the micro-signal moving coil type linear vacuum pump is mainly determined by the rigidity of the spring 8 and the mass of the piston 6 and the moving coil 3.

k＝(2πf)²m

In one embodiment, the linear pump system works at a resonance point through reasonable design of mechanical parameters, energy can be effectively utilized, and the working efficiency is highest. Further, in another embodiment, in order to improve the efficiency of the pump during operation and facilitate direct utilization of domestic electricity, the natural frequency of the mechanical system may be designed to be about 50 Hz.

In one embodiment, the minimum inlet pressure Pi is 220V/50Hz according to the AC power source_min500mbar, outlet pressure P₀1bar, suction Q_vCarrying out finite element simulation calculation on the condition of 1L/min to obtain the following main parameters of the micro moving-coil type linear vacuum pump system:

preferably, in another embodiment, the parameters of the coil 3 take the following values:

experiments prove that the miniature moving-coil linear vacuum pump can adopt 220V/50Hz civil electricity as an input power supply, has the size of less than 80mm multiplied by 70mm multiplied by 40mm, has the noise of less than 40B during working, has the maximum vacuum degree of less than 500mbar, and can be used for realizing the low vacuum of a closed space (20L) of a refrigerator.

The miniature moving-coil type linear vacuum pump has the following advantages:

Although the present invention has been described in terms of the preferred embodiment, it is not intended that the utility model be limited to the embodiment. Any equivalent changes or modifications made without departing from the spirit and scope of the present invention also belong to the protection scope of the present invention. The scope of the utility model should therefore be determined with reference to the appended claims.

Claims

1. The utility model provides a miniature moving coil formula linear vacuum pump, its characterized in that includes the cavity, is connected with cavity vacuum control mechanism on the cavity, be provided with yoke, moving coil in the cavity, the middle part of yoke is provided with axially extended piston hole, the piston is worn to be equipped with in the piston hole activity, be provided with the annular groove on the outlying yoke of piston hole, the inner wall of annular groove is interior yoke, the outer wall of annular groove is outer yoke, install the magnet on the inner wall of outer yoke, form annular space between interior yoke and the magnet, piston and moving coil fixed connection, moving coil movably extends to in the annular space, through letting in the alternating current to the moving coil, the control moving coil is followed axial reciprocating motion is to the annular space.

2. The miniature moving coil linear vacuum pump of claim 1 further comprising a moving coil motion damping means connected to the moving coil.

3. The micro moving-coil linear vacuum pump according to claim 2, wherein the moving-coil movement damping member is a spring connected between the moving coil and the inner yoke, and/or the spring is connected between the moving coil and the chamber.

4. The micro moving-coil linear vacuum pump according to claim 1, wherein the chamber body has an air inlet and an air outlet at one side thereof, the chamber body vacuum control mechanism is a check valve, and the air inlet and the air outlet are respectively provided with a check valve.

5. The micro moving-coil linear vacuum pump according to claim 1, wherein the chamber vacuum control mechanism is disposed at the top of the chamber, and the piston hole is extended upward to the chamber vacuum control mechanism at the top; or the cavity vacuum control mechanism is arranged at the bottom of the cavity, a through hole which penetrates downwards to the bottom cavity vacuum control mechanism along the axial direction is arranged on the side wall of the bottom of the cavity, and the bottom end of the piston extends into the through hole and can reciprocate in the through hole along the axial direction.

6. The micro moving coil linear vacuum pump of claim 1, wherein the piston is mounted in the piston bore by a bearing.

7. The micro moving-coil linear vacuum pump according to claim 4, wherein a sealing end cap is provided at the other side of the chamber, and a vacuum hole is provided at the sealing end cap to communicate the inside and the outside of the chamber.

8. A miniature moving coil linear vacuum pump according to any of claims 1 to 7, wherein the natural frequency of the mechanical system of said miniature moving coil linear vacuum pump is equal to the frequency of said alternating current.

9. The micro moving-coil linear vacuum pump according to claim 8, wherein the natural frequency of the mechanical system of the micro moving-coil linear vacuum pump is 50Hz or 60 Hz.

10. The micro moving-coil linear vacuum pump according to any one of claims 1 to 7, wherein the mass of the moving part in the mechanical system of the micro moving-coil linear vacuum pump is 0.2Kg, the spring rate is 19739N/m, the cylinder diameter is 12mm, the piston stroke is 6-10mm, the air gap magnetic induction is 0.3-0.35T, the coil effective length of the coil winding is 659.73m, the coil equivalent inductance is 0.01H, and the coil resistance is 1224 Ω.