CN102259088A

CN102259088A - Miniature moving-magnet vibration exciter

Info

Publication number: CN102259088A
Application number: CN2011101576151A
Authority: CN
Inventors: 张春萍; 张晓青; 郭方中; 李奎
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2011-06-13
Filing date: 2011-06-13
Publication date: 2011-11-30

Abstract

The invention provides a miniature moving-magnet vibration exciter which comprises a linear motor assembly, a compressor assembly and a hanging assembly, wherein the linear motor assembly comprises a magnet yoke pair, a magnet exciting coil and a permanent magnet ring which are concentric; the permanent magnet ring is formed by stacking up an annular axial magnet charger and a radial magnet charger; an air cylinder in the compressor assembly is fixed in the center ring of the magnet yoke pair by virtue of an air cylinder bracket; a piston is positioned in the air cylinder; the magnet yoke pair is suspended and fixed on the air cylinder bracket; the hanging assembly is a plate spring; the plate spring is formed through cutting by adopting the involute of a circle; the involute of the circle extends to the outside diameter of the plate spring so that the plate spring is divided into three cantilevers; the adjacent cantilevers are connected into a whole by virtue of a plate spring baffle ring; and the bottom of the piston is fixed at the center hole of the plate spring by virtue of a plate spring gasket. By virtue of a plate spring suspending structure and a magnet yoke positioning way, the coaxiality can be flexibly adjusted in an assembly process; the processing requirements on a part are decreased; the whole device has a simple structure; the molded line of the plate spring is improved; and the moving-magnet vibration exciter has the advantages of stronger stability and long service life.

Description

Miniature moving-magnet exciter

Technical field

The present invention relates to a kind of moving-magnet exciter, it is with upper frequency, less quality and volume operation, be applicable to miniature dynamic power machine (comprising minisize refrigeration and low temperature machinery), need to produce the device of exciting force in small-sized and miniature pacemaker and reciprocating pump and the fields such as acoustics, low-temperature biological and medical science.

Background technology

The traditional thermal power technology of the sternness an urgent demand of energy scarcity and environmental protection develops to pollution-free and direction renewable energy utilization, wherein, can utilize the Stirling of low-grade heat source, nothing or few moving component and thermo-acoustic technology is one of the most potential developing direction.In solar electrical energy generation, silion cell can only utilize the synthetic energy of its photosynthesis, and Stirling and thermo-acoustic technology then can utilize the net quantity of heat in the solar energy, and this is extremely important to the utilization ratio that improves solar energy; In addition, common industrial waste heat utilizes method to involve great expense, and utilization ratio is low, adopts Stirling and thermo-acoustic technology then can effectively utilize the very high energies that contains in the used heat, and reduces cost.And along with the development of high temperature superconducting materia and high density integrated circuit having information technology, the power density of various electric appliance and electronic equipment and the heat flow density of unit are sharply increase, it is little to press for size, cooling capacity is strong, the reliability height, and can carry out mini refrigerating machine independent or concentrated cooling to the parts that need in the electronic equipment to lower the temperature.And miniature Stirling and hot sound refrigerating machine have higher frequency, and this utilization to regenerative resource is very crucial.In addition, along with developing rapidly of cryogenic technique, refrigeration machine increases day by day in microminiaturization, lightweight, demand aspect integrated.Cryo Refrigerator such as sterlin refrigerator, vascular refrigerator etc. commonly used at present all are faced with an important problem, the i.e. microminiaturization in its external excitation source in the process of microminiaturization.And the volume of the drive units such as compressor of various traditional forms commonly used is bigger at present, has been difficult to satisfy the light-weighted demand of micromachine.In order to solve the constant even raising of the property retention that in the process that reduces complete machine weight, volume, makes drive unit, be necessary to research and develop a kind of new and effective vibrator and replace reciprocating-piston compressor commonly used at present.

Since late 1970s Britain ox Feng university successfully develops ox Feng type sterlin refrigerator, adopting linear linear electric motors is the external excitation source, designs simplification, long working life, the modern stirling refrigeration technology that reliability is high have obtained the development of emphasis and have paid close attention to widely.For the Stirling and the hot sound refrigerating machine that adopt regenerator as power conversion and reservoir part, its key is that regenerator makes in the linear compressor piston and cylinder can only use oil-free lubrication, this requires that good axiality is arranged between the two, and this need rely on accurate design and processing technology to guarantee, not only increase the cost of complete machine, also made its microminiaturized difficulty strengthen.Therefore, simplify the design and the processing technology of complete machine, make its axiality in assembling, can adjust the process that to accelerate Stirling and hot sound refrigerating machine microminiaturization effectively.

In recent years, linear compressor replaces traditional reciprocating compressor as pressure wave generator just gradually with its compact conformation, efficient height, long characteristics of life-span.Can be divided into three kinds of moving-iron type, moving-coil type and moving-magnetic types to linear compressor according to the dissimilar of movable body in the vibrator.Moving-iron type seldom is used at present because the quality of mover is bigger.Moving-coil type complete machine size is big, and quality is bigger, because the reciprocating motion of its mover coil causes the lead-in wire frangibility in the coil, therefore only is applicable to the low frequency refrigeration machine not high to the vibrator dimensional requirement.The magnet of moving-magnetic type vibrator directly links to each other with piston, coil becomes the part of stator, has simplified the design and the assembling of complete machine, has reduced the volume and the quality of complete machine, can realize that the higher-order of oscillation and reliability are higher, therefore more and more be applied in the Cryo Refrigerator.

Find by literature search, publication number is CN201110257, name is called the patent application of moving-magnet exciter, belong to a kind of moving-magnetic type compressor, its version is propped up the coil that hangs spring, yoke and inside thereof for column is housed in cylindrical housing, cylinder embeds the cylinder flange, and cylinder flange and shell centering cooperate, piston in the cylinder is fixedlyed connected with piston rod, and the coil supports of passing yoke and inside thereof is propped up in column and hung spring center.It is characterized in that adopting two axially and the permanent magnet of a radial magnetizing as permanent-magnetic clamp, the matched in clearance of piston and permanent-magnetic clamp location relies on column to prop up and hangs spring and cylinder flange.This invention improves magnetic field intensity by arranging the novel permanent magnetic loop type, utilize column to prop up to hang spring and do suspended structure, but it is not enough to hang the radial rigidity of spring, can't satisfy the high-axiality requirement, make piston be in operation and easily depart from its center, deflect and hit cylinder; In addition, its complete machine axiality is unadjustable, needs accurately each part dimension of design, and guarantees rational assemble sequence and technology, has increased processing and assembly difficulty.

Chinese invention patent application publication number CN1773112A proposes a kind of moving-magnetic linear compressor, comprise a straight line electric machine assembly, mainly contain interior outer yoke, moving magnetic filed, permanent magnet and the electric mover carriage of concentric combining structure, permanent magnet is arranged on the motor mover carriage and is in the magnetic field that is made of outer yoke.The flexible leaf spring that has been characterized in adopting novel molded lines is as long-armed suspended structure and be provided with the crashproof cylinder mechanism of compressor.Though adopt the flexible leaf spring of novel molded lines to be convenient to guarantee the axial displacement of leaf spring, first its involute extends near leaf spring extension place and has just stopped, and forms long-armed root.When leaf spring was done axial displacement, involute is long-armed to be reversed around its horizontal axis.When spring was in maximum displacement place, the fatigue stress maximum of root made root rupture.Second, the crashproof cylinder mechanism of rubber anti-collision sheet is pasted in employing on electric mover carriage and plane that inner yoke may contact, to the size of each part reasonably be designed in advance, could guarantee that the distance in the gap that forms between electric mover carriage and the inner yoke equals the compression travel of piston when the equilbrium position.The 3rd, long-armed reversing must make the vertical axis of leaf spring swing, and therefore, it is very difficult guaranteed that the axiality of complete machine only relies on the accuracy of design size and processing.

Summary of the invention

The present invention is directed to the deficiencies in the prior art and defective, a kind of miniature moving-magnet exciter has been proposed, by spiral spring overhung construction and yoke locate mode, when assembling, can adjust axiality flexibly, reduced processing request to part, automatically adjust and absorb the eccentric and vibration that moving-magnet exciter is in operation and is produced by the elastic compression ring structure, make whole apparatus structure simple, stability is stronger; Improved the molded lines of spiral spring, improved the fatigue strength of spiral spring, made the longer service life of moving-magnet exciter.

Miniature moving-magnet exciter comprises casing 40 and is placed in its interior linear motor assembly 10, compressor assembly 20, suspension assembly 30,

Linear motor assembly 10 comprises that coaxial mounted yoke is to, magnet exciting coil 13 and magnet ring, give magnet exciting coil 13 energisings, the excitation yoke is to producing magnetic field, and magnet ring is arranged in the magnetic field of yoke to producing, and magnet ring is stacked alternately by the axial charging body of ring-type and radial magnetizing body and constitutes;

Compressor assembly 20 comprises cylinder 21, cylinder support 22, piston 23 and non-magnetic conduction ring flat-plate 25, and cylinder 21 is positioned on the non-magnetic conduction ring flat-plate 25 by 22 suspentions of cylinder support, and piston 23 is positioned at cylinder 21; Magnet ring is fixed on the piston rod of piston 23, and yoke is positioned on the non-magnetic conduction ring flat-plate 25 suspention;

Suspension assembly 30 comprises that being positioned at flexible spiral spring 31, the reed molded lines of cylinder 21 upper fixed on casing 40 inwalls adopts the circle involute cutting to form, its involute extends to the reed external diameter always, reed is divided into three cantilevers, adjacent cantilever joins together by the spiral spring baffle ring, and the central hole of flexible spiral spring is fixed on the piston rod top of described piston 23;

Have intake valve 45 on the described casing, cylinder 21 bottoms have air bleeding valve 46.

Further, casing 40 and yoke to the space in be provided with elastic thread hold-down ring 44, between casing 40 and cylinder support 22, flat spring baffle ring, be provided with elastic compression ring 42.

Further, described yoke is to comprising upper magnet yoke and lower yoke, and magnet exciting coil 13 is embedded in the groove between the lower yoke, and magnet ring is between piston 23 and cylinder 21.

Further, magnet ring is stacked alternately by the radial magnetizing body of the axial charging body of two ring-types and a ring-type and constitutes.

Further, with two opposed installations of miniature moving-magnet exciter.

Technique effect of the present invention is embodied in: 1, magnetic structure is stacked by the hollow magnet ring symmetry of axial and radial magnetizing and constitutes, this structure can be brought into play the high-coercive force of Rubidium iron boron material better, can reduce the residual non-equilibrium cross force that is applied on the mover again effectively, reduce the mechanical eccentric of mover with respect to center longitudinal axis, make flux concentration in the central area, bring into play the useful work of magnet exciting coil to greatest extent, reduce the leakage field loss, improve magnetic field intensity gradient.Therefore, adopt this structure, not only make whole device expend less material, volume is littler, and quality is lighter, the more important thing is and can improve vibrator power output constant, effectively improves the performance of vibrator.2, adopt flexible spiral spring suspention piston, and with non-magnetic conduction ring flat-plate suspension cylinders support and last lower yoke, when assembling, pass through the minimum current in the monitoring magnet exciting coil, seek the optimum assembling orientation of yoke, guarantee the axiality that piston rod and cylinder are in operation, and fix, make the coaxial error propagation that in processing and assembling, occurs with laser curing technology, when assembling, obtain adjusting and compensation, make axiality no longer only depend on machining accuracy.3, the molded lines to spiral spring improves, and its involute is extended on the external diameter of reed always, reed is divided into three cantilevers, to hide tired cross section and stress concentration point.4, the hold-down ring of being made by elastomeric material is set between casing and cylinder support, flat spring baffle ring; In the space between casing and upper and lower yoke the hold-down ring of being made by elastomeric material is set also, and fix by the mode and the casing that are threaded, utilize this two places elastic material part to absorb vibrator electric machine assembly, compressor assembly, suspention assembly and shell vibration energy when operation, keep the axiality of complete machine constant.5, adopt spiral spring to do the suspension and support of mover, magnet exciting coil is placed in the yoke, magnet ring is placed between piston and the cylinder, can greatly reduce complete machine size and quality, realize the purpose of slim reluctance motor.6, can be according to the opposed layout electric machine assembly of power and field of employment, compressor assembly and suspention assembly, be used for middle-size and small-size Stirling and hot sound refrigerating machine, or be combined into powerful cascade tube, make its adaptability extensive, not only can be used for the mini refrigerating machine in photoelectron technology, superconductor technology and the space telecommunication technique, also can be applicable in pacemaker, medical oxygen producing system and the medical refrigerator, also can combine with regenerative resource simultaneously as novel drive unit such as solar heat phonomotor, refrigeration machine etc.7,, can improve the power output of moving-magnet exciter and be applicable to different loads and application places by taking the opposed mode of assembly.

Description of drawings

Fig. 1 is a structural representation of the present invention.

Fig. 2 is one embodiment of the present of invention schematic diagrames.

Fig. 3 is that magnet ring of the present invention is arranged schematic diagram.

Fig. 4 is a flexible spiral spring molded lines schematic diagram of the present invention.

Fig. 5 is an alternative embodiment of the invention schematic diagram.

Fig. 6 is first opposed type embodiment schematic diagram of the present invention.

Fig. 7 is second opposed type embodiment schematic diagram of the present invention.

Fig. 8 is the 3rd an opposed type embodiment schematic diagram of the present invention.

The specific embodiment

As depicted in figs. 1 and 2, embodiment of the invention moving-magnetic type vibrator comprises: linear motor assembly 10, compressor assembly 20, suspension assembly 30 and casing 40.

Linear motor assembly 10 comprises: axial charging permanent magnet 11, and radial magnetizing permanent magnetism body 12, magnet exciting coil 13, upper magnet yoke 14, lower yoke 15, as shown in Figure 3.Permanent magnet is made by Rubidium iron boron material, adopt six or eight accurate radially oriented magnetic structures that parallel-oriented fan-shaped permanent magnet blocks is spliced, be bonded on the piston rod 23, magnet exciting coil 13 is embedded in the groove of upper magnet yoke 14 and lower yoke 15 formation in the form of a ring, last lower yoke adopts silicon steel sheet to make, axial permanent magnetic body 11, radial permanent magnet body 12, coil 13 and upper magnet yoke 14, the complete magnetic circuit of lower yoke 15 common formation.

Compressor assembly 20 comprises cylinder 21, cylinder support 22, and piston rod 23, piston head 24, non-magnetic conduction ring flat-plate 25, as shown in Figure 2.The piston that is made of piston rod 23 and piston head 24 adopts the nonmagnetic steel material to make, be structure as a whole, to reduce the concentric error transmission, and when need guaranteeing assembling and cylinder leave certain clearance, cylinder support 22 is an one with cylinder, and acutangulate crossing, after having assembled suspention assembly 30 and piston rod 23 and

magnet ring

11 and 12, pass to low-voltage for magnet exciting coil 13, the low frequency alternating current, under the effect of magnetic field,

permanent magnet

11,12 drive piston rod 23 moves back and forth, when piston rod 23 moves smooth and easy and cylinder 21 collisionless, by the electric current minimum of magnet exciting coil, be positioned cylinder support 22 non-magnetic conduction ring flat-plate on laser curing technology this moment, to guarantee the coaxial concentric of piston rod 23 and cylinder 21.Be carved with radially wire casing at non-magnetic guiding loop backboard face, locate in order to give the every silicon steel sheet that constitutes yoke, and between silicon steel sheet and non-magnetic conduction ring flat-plate, evenly coat high-temperature-resistant epoxy resin and fixed.

Suspension assembly 30 comprises flexible spiral spring 31, is made of spiral spring baffle ring 32, spiral spring liner 33 and piston rod riveted joint sheet 34 the multi-disc reed.As shown in Figure 4, the reed of spiral spring adopts the circle involute cutting to form, and its involute extends to the reed external diameter always, and reed is divided into three cantilevers, and adjacent cantilever joins together by the spiral spring baffle ring.After the alignment of multi-disc spiral spring molded lines, adopt the spiral spring liner to fix its centre bore.After the spiral spring assembling finishes, utilize the soldering of lower temperature that piston rod is fixed on the spiral spring liner by piston rod riveted joint sheet again.Spiral spring adopts spring steel or beryllium-bronze material to make, and will carry out annealing in process, to guarantee to have enough intensity.

Case component 40 comprises support 41, support rim 42, elastic compression ring 43, elastane thread hold-down ring 44, and is installed in the air bleeding valve 46 in intake valve 45 on the support 41 and cylinder 21 outlets.Spiral spring baffle ring 32 is contained on the support rim 42 of bottom of shell, and piston rod 23 passes from the centre bore of spiral spring 31, connects fixing by piston head riveted joint sheet 33 and spiral spring 31.Elastic compression ring 43 is filled in by being slidingly matched between the gentle jar support of support rim of casing, have internal thread at inboard wall of base face and yoke equal-height position, elastic compression ring 44 outside wall surface have external screw thread, cooperation by internal and external threads, elastic compression ring 44 and support 41 are screwed, after electric machine assembly 10, compressor assembly 20, suspension assembly 30 assemblings finish, by freely stretching of elastomeric material, can guarantee that electric machine assembly 10, compressor assembly 20, the suspention assembly 30 of vibrator when operation keeps coaxial concentric with casing 40, do not hit the cylinder incident.

Fig. 5 is an alternative embodiment of the invention schematic diagram, suspension assembly 30 is made of two groups of spiral elastic parts, between two groups of spiral spring assemblies, be furnished with elastic compression ring 44, adjust the axiality between casing and the two groups of spiral spring assemblies by being slidingly matched, piston rod 23 passes the centre bore 31 of two groups of spiral spring assemblies successively, rivet sheet 33 by piston rod and fix, be applicable to little still the place of the displacement request of piston to having relatively high expectations service life with spiral spring 31 connections.

Fig. 6, Fig. 7 are two kinds of opposed type embodiment schematic diagrames of the present invention, and by two linear motor assemblies, compressor assembly and suspension assembly symmetric arrangement, the running frequency of two compressor assemblies and phase place can be adjusted, and are suitable for using in the place of high-power or cascade.

Fig. 8 is another opposed type embodiment schematic diagram of the present invention, suspension assembly 30 is made of one group of multi-disc spiral spring assembly, the piston that is made of piston rod 23 and two piston heads 24 adopts the nonmagnetic steel material to make, be structure as a whole, to reduce the concentric error transmission, and leave certain clearance with cylinder when guaranteeing assembling, be applicable in the use of the place of high-power or cascade.

Claims

1. miniature moving-magnet exciter comprises casing (40) and is placed in its interior linear motor assembly (10), compressor assembly (20), suspension assembly (30), it is characterized in that;

Linear motor assembly (10) comprises that coaxial mounted yoke is to, magnet exciting coil (13) and magnet ring, give magnet exciting coil (13) energising, the excitation yoke is to producing magnetic field, magnet ring is arranged in the magnetic field of yoke to producing, and magnet ring is stacked alternately by the axial charging body of ring-type and radial magnetizing body and constitutes;

Compressor assembly (20) comprises cylinder (21), cylinder support (22), piston (23) and non-magnetic conduction ring flat-plate (25), and cylinder (21) is positioned on the non-magnetic conduction ring flat-plate (25) by cylinder support (22) suspention, and piston (23) is positioned at cylinder (21); Magnet ring is fixed on the piston rod of piston (23), and yoke is positioned on the non-magnetic conduction ring flat-plate (25) suspention;

Suspension assembly (30) comprises that being positioned at flexible spiral spring (31), the reed molded lines of cylinder (21) upper fixed on casing (40) inwall adopts the circle involute cutting to form, its involute extends to the reed external diameter always, reed is divided into three cantilevers, adjacent cantilever joins together by the spiral spring baffle ring, and the central hole of flexible spiral spring is fixed on the piston rod top of described piston (23);

Have intake valve (45) on the described casing, cylinder (21) bottom has air bleeding valve (46).

2. miniature moving-magnet exciter according to claim 1, it is characterized in that, casing (40) and yoke to the space in be provided with elastic thread hold-down ring (44), between casing (40) and the cylinder support (22), be provided with elastic compression ring (42) between casing (40) and the flat spring baffle ring.

3. miniature moving-magnet exciter according to claim 1 is characterized in that, described yoke is to comprising upper magnet yoke and lower yoke, and magnet exciting coil (13) is embedded in the groove between the lower yoke, and magnet ring is positioned between piston (23) and the cylinder (21).

4. according to claim 1 or 2 or 3 described miniature moving-magnet exciters, it is characterized in that magnet ring is stacked alternately by the radial magnetizing body of the axial charging body of two ring-types and a ring-type and constitutes.

5. according to claim 1 or 2 or 3 described miniature moving-magnet exciters, it is characterized in that, two opposed installations of miniature moving-magnet exciter.