CN102713467A

CN102713467A - Cryogenic refrigerator

Info

Publication number: CN102713467A
Application number: CN2010800616174A
Authority: CN
Inventors: 朴圣云; 郑圆铉
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2010-02-24
Filing date: 2010-12-02
Publication date: 2012-10-03
Anticipated expiration: 2030-12-02
Also published as: WO2011105681A1; KR20110097065A; CN102713467B

Abstract

According to the present invention, a cryogenic refrigerator comprises: a sealed shell; a fixed member which is arranged in the sealed shell and which includes a cylinder; a movable member including a piston which reciprocates in an axial direction within the cylinder, and a displacer which reciprocates in the direction opposite to the piston; a permanent magnet connected to the piston; and an inner stator and an outer stator which are installed to maintain air gaps between the permanent magnet and the inner and outer stators, and which enable the permanent magnet to reciprocate by mutual electromagnetic force, wherein the inner stator is fixed so as to contact an outer surface of the cylinder, and the outer stator is fixed at an inner surface of the sealed shell. According to the present invention, the inner stator and the outer stator can be firmly installed to achieve improved operating reliability of the cryogenic refrigerator.

Description

Ultra-low temperature refrigerating device

Technical field

The present invention relates to a kind of ultra-low temperature refrigerating device, relating in particular to can be through the ultra-low temperature refrigerating device that structure is raised the efficiency that is provided with of improved cylinder and inner stator.

Background technology

Usually; Ultra-low temperature refrigerating device is as the low vibration, the high reliability refrigeration machine that are used for cool small electronic component or superconductor etc.; Processes such as the compression of the working fluid through helium or hydrogen etc. or expansion produce refrigeration work consumption, and that is widely known by the people representative has sterlin refrigerator (Stirling refrigerator) and GM refrigeration machine (GM refrigerator) or a joule-thomson refrigeration machine (Joule-Thomson refrigerator) etc.This refrigeration machine not only exists in the problem that its reliability reduces when running up, and the wearing and tearing for reply friction position when also having running need lubricated separately problem.Therefore; Need a kind ofly can not only in running up, keep its reliability; But also need not separately ultra-low temperature refrigerating device lubricated, that can for a long time not keep in repair, the working fluid of suitable in the recent period is high pressure plays the unlubricated ultra-low temperature refrigerating device that a kind of bearing is used for reducing the friction between the part.

This ultra-low temperature refrigerating device constitutes, and in compression stroke, cold-producing medium is compressed, extracts, and after heat radiation and regenerative process, expands in the expansion space, through the heat exchange action with surrounding air environment temperature is maintained the ultralow temperature state.At this moment, ultra-low temperature refrigerating device comprises: cylinder, the compression stroke of formation cold-producing medium; Piston carries out linear reciprocating motion in the inboard of cylinder; And linear electric machine, piston is driven, this linear electric machine is made up of inner stator and external stator and permanent magnet.

Summary of the invention

Technical problem

What the object of the present invention is to provide inner stator and external stator in ultra-low temperature refrigerating device in the past preferably is provided with structure, improves the operating reliability of ultra-low temperature refrigerating device.

The means of dealing with problems

The ultra-low temperature refrigerating device of the present invention that is used to address the above problem is characterized in that, comprising: closed shell; Fixed part, it is located at the inside of closed shell, and this fixed part comprises cylinder; Movable member, the displacer of linear reciprocating motion, permanent magnet are carried out along the piston that axially carries out linear reciprocating motion with along the direction opposite with piston in its inboard that is included in cylinder; It is connected with piston; And inner stator and external stator, be set to keep the gap with permanent magnet, by mutual electromagnetic power permanent magnet is back and forth driven; Inner stator is fixed in the outer peripheral face of cylinder with the mode that can contact, and external stator is fixed in the inner peripheral surface of closed shell with the mode that can contact.

Here, preferably, ultra-low temperature refrigerating device comprises leaf spring, and this spring supports displacer; Leaf spring is fixed in external stator through miscellaneous part.

Simultaneously, preferably, ultra-low temperature refrigerating device comprises support, and an end of this support is by the edge of bolt in leaf spring; The other end of support is fixedly welded on external stator.

Simultaneously, preferably, closed shell comprises the package of drum and is fixedly welded on the framework on this package; External stator is fixedly welded on framework.

More preferably, ultra-low temperature refrigerating device can comprise a plurality of adhesion grooves, and above-mentioned a plurality of adhesion grooves are arranged at the outer peripheral face of cylinder, is used to accommodate inner stator is fixed in the adhesive on the outer peripheral face of cylinder.

And, adhere to groove and can have the ring-type that forms in a circumferential direction along the outer peripheral face of cylinder.

And, a plurality of adhesion grooves can cylinder axially on have predetermined distance.

And the cross section of a plurality of adhesion grooves forms, and along with the degree of depth apart from the outer peripheral face of cylinder deepens, its width just narrows down.

And, can only be coated with epoxy resin in the inside that adheres to groove.

The effect of invention

The ultra-low temperature refrigerating device of the present invention that constitutes as stated is only after the adhesion groove of the outer peripheral face of being located at cylinder applies the adhesive as epoxy resin etc.; Because inner stator is fixed when pressing from both sides the outer peripheral face that is bonded at cylinder; Thereby can prevent that adhesive from leaking when can reduce the use amount of adhesive between inner stator and cylinder; Not only can firmly fix inner stator and can also prevent the disengaging of inner stator, thereby have the advantage that can ensure operating reliability.

Description of drawings

Fig. 1 is the side view that a preferred example of ultra-low temperature refrigerating device of the present invention is shown.

Fig. 2 is the side sectional block diagram that a preferred example of ultra-low temperature refrigerating device of the present invention is shown.

Fig. 3 is the side sectional view that a preferred example of ultra-low temperature refrigerating device of the present invention is shown.

Fig. 4 is the exploded view of fixed structure that the preferred inner stator of ultra-low temperature refrigerating device of the present invention is shown.

The specific embodiment

Below, will specify embodiments of the invention with reference to accompanying drawing.

Fig. 1 to Fig. 3 is the figure that an example of ultra-low temperature refrigerating device of the present invention is shown.

To shown in Figure 3, an example of ultra-low temperature refrigerating device of the present invention comprises like Fig. 1: shell (case) 10, and it is used to form outward appearance; Fixed part 20, it is fixed in the inside of shell 10, forms predetermined space; Movable member 30, its compression stroke C in fixed part 20 is along axially carrying out linear reciprocating motion and cold-producing medium being compressed and expands; Linear electric machine (linear motor) 40, it is arranged between shell 10 and the fixed part 20, comes driving movable parts 30; Regenerator 50, it axially combines with movable member 30, realizes equal-volume regeneration between the cold-producing medium that flows with mutually opposite direction; Radiating part 60, it is installed on the periphery of fixed part 20 and movable member 30 and regenerator 50, the heat of distributing compressed cold-producing medium to the outside; Cooling end 70, it is along axially combine to absorb outside heat to form expansion space E, to make the cold-producing medium that expands with regenerator 50.

Shell 10 comprises with regenerator 50, radiating part 60 and cooling end 70 package (shell tube) 12 of the drum that forms concentric framework (frame) 11, fixes along axially being connected with framework 11.Framework 11 preferably links to each other through welding with package, and portion forms closed shell within it.Even fixed part 20 is littler than package 12 by the formed diameter of the fastening part of screw in framework 11, but its thickness is very thick, in order to improve heat exchanger effectiveness, the formed thickness of part that radiating part 60 is installed in framework 11 is thinner relatively.At package 12 predetermined pipe 13 is provided, be in the vacuum state of height for the inside that makes shell 10 through exhaust after, inject the cold-producing medium of pure helium (He) gas etc., therefore be provided for exhaust or be used to inject the pipe 13 of cold-producing medium.In addition, package 12 also has the power supply terminal 14 to linear electric machine 40 supply power supplys.

Fixed part 20 is included in the cylinder (cylinder) 21 that extends to the inboard of package 12 when being fixed in framework 11, extends the displacer outer cover (displacer housing) 22 that matches with the inboard with framework 11 from cylinder 21.Cylinder 21 is the drum that difference in height is arranged with displacer outer cover 22, and the diameter of displacer outer cover 22 is less than the diameter of cylinder 21, is fixed in framework 11 from the coupling part that the outer peripheral face of cylinder 21 extends by screw.At this moment, cylinder 21 will form the compression stroke C of compressed refrigerant in inside with displacer outer cover 22, and have through hole 21h, the 22h that is communicated with the heat-dissipating space D of the inboard of radiating part 60 respectively.

The inside that movable member 30 is included in cylinder 21 by after the linear electric machine 40 stated drive and carry out linear reciprocating motion piston (piston) 31, the internal condition of displacer outer cover 22 to the action-reaction law of the linear reciprocating motion of piston 31 link along carrying out the displacer (displacer) 32 of linear reciprocating motion with the direction in the opposite direction of piston 31.Piston 31 stays gap piston only (piston body) 311 that is provided with and the piston plug-in unit (piston plug) that is arranged on the inboard of piston only 311 312 to constitute by the inner peripheral surface at cylinder 21.Displacer 32 is by the displacer rod (displacer rod) 321 that in the center that connects piston plug-in unit 312, is supported through the leaf spring S available buffer ground that is fixed in shell 10 with along axially accommodating/be combined in the displacer body 321a of end that conduct is built in the displacer rod 321 of displacer outer cover 22; The displacer lid (displacer cover) 322 that forms the predetermined space that makes flow of refrigerant constitutes, and between piston 31 and displacer body 321a, forms compression stroke C.At this moment; The cross section of displacer body 321a has the 1st through hole 321h, the 2nd through hole 321H that is communicated with the inboard of radiating part 60 when being " U " font; And displacer lid 322 not only has the displacer valve 323 that the pressure differential by the suction inlet (not shown) that is communicated with regenerator 50 opens and closes, and also has the through hole 322H that is communicated with the inboard of displacer body 321a.

On the other hand, because movable member 30 carries out linear reciprocating motion, thereby except leaf spring S, also adopt the lubricated gas bearing of part that can make mutual friction, the structure that is constituted is following.The stream 312a that the cold-producing medium that can make compression stroke C along axially having of piston plug-in unit 312 flows into; And have therewith a plurality of accumulator tank 312b that the outer peripheral face along piston plug-in unit 312 that is communicated with forms by circumferencial direction; And having a plurality of hole 311h that radially connect by piston only 311, the feasible cold-producing medium that is stored in the accumulator tank 312b of piston plug-in unit 312 is fed to the space between piston only 311 and the cylinder 21; And having a plurality of hole 312h that radially connect that press piston plug-in unit 312, the feasible cold-producing medium that is stored in the accumulator tank 312b of piston plug-in unit 312 is fed to the space between piston plug-in unit 312 and the displacer rod 321.Certainly; For the cold-producing medium of the accumulator tank 312b that will be stored in piston plug-in unit 312 is guided to the hole 311h of piston only 311 or the hole 312h of piston plug-in unit 312; By circumferencial direction or axially have the groove (not shown) of variform, the piston valve (not shown) that can make the cold-producing medium one-way flow is provided between compression stroke C and accumulator tank 312b at the outer peripheral face of piston plug-in unit 312.

Linear electric machine 40 comprises: cylindrical shape inner stator (inner stator) 41, and it is fixed in the outer peripheral face of cylinder 21 with the mode that can contact; Cylindrical shape external stator (outer stator) 42, it is fixed in the inner peripheral surface of package 12 with the mode that can contact, so that keep predetermined distance with the outside of inner stator 41; Permanent magnet 43, it is connected with piston only 311, so that keep the predetermined distance between inner stator 41 and the external stator 42.Certainly, external stator 42 is equipped with a plurality of pellets (core block) 422 at coil coiling body 421, and this coil coiling body 421 is connected with the power supply terminal 14 of shell 10 sides.One end of the pellet 422 of external stator 42 is supported by framework 11, and preferably through being fixedly welded on framework 11, the other end is supported by support 16.Support 16 is fixed in the periphery of leaf spring S by screw.That is, an end of external stator is supported by framework 11, and the other end is supported by the support 16 that is connected with leaf spring S.

Regenerator 50 comprises: regeneration outer cover 51, and it combines with displacer outer cover 22, cylindrical shape; Heat-storing material 52, it is inserted into the part of displacer body 321a and the inboard of regeneration outer cover 51; End cap (end cap) 53, its ground, end that can hide heat-storing material 52 adheres to.Cold-producing medium can be through heat-storing material 52 and end cap 53.Carry out heat exchange and come the effect of return again after the accumulation of energy because heat-storing material 52 plays through contact with refrigerant gas; Therefore heat exchange area and specific heat is big but also heat transfer coefficient is little not only; Preferably constitute by material with uniform gas permeability, as an example, can be by the morphosis of fine rule group.

Radiating part 60 constitutes by the base of drum 61 and along the plate shape fin 62 that circumferencial direction closely is arranged in this base 61, is formed by the metal material of the high copper of heat transference efficiency etc.

Cooling end 70 is installed in the end of regenerator 50, so as can and end cap 53 between form expansion space E, keep ultralow temperature through heat exchange action.Certainly, cooling end 70 can constitute, and forms the surface area of broad for the effect of between the cold-producing medium of inside and air outside, playing heat exchange.

In addition, shown in the unaccounted Reference numeral 80 is passive equilibrium device (passive balancer), and this passive equilibrium device can comprise the leaf spring of the vibration of the closed shell that minimizing produces when the running ultra-low temperature refrigerating device.

Watch running, as follows like the ultra-low temperature refrigerating device of above-mentioned formation.

At first, if supply power supplys through power supply terminal 14 to external stator 42, then can between inner stator 41 and external stator 42 and permanent magnet 43, produce electromagnetic force mutually, permanent magnet 43 will carry out linear reciprocating motion by this electromagnetic force.At this moment, be connected because permanent magnet 43 reaches the piston plug-in unit 312 that matches therewith with piston only 311, thereby piston 31 will carry out linear reciprocating motion with permanent magnet 43.Therefore; In case piston 31 carries out linear reciprocating motion in the inside of cylinder 21; According to action-reaction law; Displacer 32 will carry out rightabout motion to the motion of piston 31, simultaneously obtain resiliency supported by leaf spring S, will carry out the linear reciprocating motion with the reverse movement direction of piston thus.

Therefore; The following process of process: through the rightabout linear reciprocating motion of piston 31 and displacer 32; In the compression stroke C compressed refrigerant of the inside of cylinder 21, pass the through hole 21h of cylinder 21, the isotherm compression process of utilizing radiating part 60 to dispel the heat in the time of via the heat-dissipating space D of the inboard of framework 11.When compression stroke C is compressed; Because displacer body 321a also together moves with the heat-storing material 52 of regenerator; Thereby in the expansion space inside of E forms relative negative pressure; Make the inside that flow into the heat-storing material 52 of regenerator through the 1st through hole 321h of the cold-producing medium of isotherm compression process through hole 22h and the displacer body 321a through displacer outer cover 22, the cold-producing medium that flows with its rightabout plays heat exchange action through the equal-volume regenerative process.When transferring to expansion space E and be inflated through the cold-producing medium of equal-volume regenerative process through isothermal expansion process at cooling end 70 cooling extraneous airs.After this; The cold-producing medium of process isothermal expansion process flow into the inside of regenerator 50 again in the process of expansion space E compression stroke C of compressed relatively while relative expansion after, through the equal-volume regenerative process of regenerating along the mobile cold-producing medium of rightabout as the utilization of above-mentioned explanation.At this moment; Cold-producing medium through the suction inlet and the inside of displacer valve 323 of being located at displacer lid 322 via displacer body 321a and displacer lid 322 after, flow into compression stroke C again through the through hole 322H of displacer lid 322 and the 2nd through hole 321h of displacer body 321a.Certainly, in the process of linear electric machine 40 runnings, incite somebody to action above-mentioned repeatedly isotherm compression process, equal-volume regenerative process, isothermal expansion process and equal-volume regenerative process successively, so that realize the ultralow temperature cooling at cooling end 70.

On the other hand; As above aforementioned; Along with the piston that constitutes movable member 30 31 and displacer 32 carry out rightabout linear reciprocating motion according to the law of action and reaction and the influence of the leaf spring that is used to support displacer 32, and carry out repeatedly compression stroke C volume-diminished, become big, the cold-producing medium of compression stroke C not only flows to regenerator 50 directions; Also flow, play the lubricated gas bearing effect of part that makes mutual sliding-contact to its rightabout.Specifically, via the cold-producing medium that heat-dissipating space D flows to regenerator 50 1 sides, between displacer outer cover 22 and displacer body 321a, play the gas bearing effect from compression stroke C; Flow to the cold-producing medium of accumulator tank 312b from compression stroke C through the stream 312a that axially are provided with at piston plug-in unit 312, flow to through the hole 311h that radially connects at piston only 311 and flow to the effect of playing gas bearing between piston plug-in unit 312 and the displacer rod 321 through the hole 312h that radially connects at piston plug-in unit 312 when playing the gas bearing effect between piston only 311 and the cylinder 21.

Especially; Watch the inner stator 41 of the drum that constitutes linear electric machine 40 and the fixed structure of external stator 42; At first, with regard to external stator 42, an end of pellet 422 is fixedly welded on framework 11; The other end then is fixedly welded on support 16, makes the outer peripheral face of pellet 422 be fixed in the inner peripheral surface of closed shell with the mode that can contact.As in cross section shown in Figure 3, confirming; Support 16 is the parts that are formed with the drum of

flange part

16a, 16b at upper and lower side respectively; The upper surface of the 16a of upper end flange portion be fixedly welded on pellet 422 the other end below, the 16b of lower end flange portion is fixed in the edge of leaf spring S by screw.Therefore, leaf spring S is fixed under the state of support 16 at its edge, but the end of resiliency supported displacer rod 321 under the state that pellet 422 is supported by framework 11 and support 16 respectively at two ends, is fixed in the inner peripheral surface of package 12 with the mode that can contact.

Then, inner stator 41 is fixed in the outer peripheral face of cylinder 21 through adhesive, and as stated, permanent magnet 43 is arranged on the gap between inner stator 41 and the external stator 42.

But; Behind the whole adhesive that applies epoxy resin etc. of the outer peripheral face of the cylinder 21 of drum; The inner stator of drum 41 is inserted and when sticking to the outer peripheral face of cylinder 21; In the time, inner stator 41 can take place is sandwiched in cylinder 21 adhesive of epoxy resin etc. outwards extrude or cylinder and inner stator between the vacuum forming process before injecting cold-producing medium, implemented of the epoxy resin phenomenon (Outgassing) of being leaked; Even therefore use a large amount of adhesives also can reduce the adhesion property between cylinder and the inner stator, inner stator might break away from from cylinder.Therefore; In a preferred embodiment of the invention; As shown in Figure 4, have a plurality of adhesion groove 21a at the outer peripheral face of the cylinder 21 of drum, only adhere to after groove 21a applies the adhesive of epoxy resin etc. at these; If inner stator 41 is clipped in cylinder 21 outer peripheral faces both are matched, then inner stator 41 adheres to and is fixed in cylinder 21.Certainly, except epoxy resin, can also use other adhesives.

In more detail, a plurality of adhesion groove 21a have the ring-type that forms in a circumferential direction along the outer peripheral face of cylinder 21, cylinder 21 axially on have predetermined distance and form.At this moment; Enlarge the face that contacts with the inner peripheral surface of inner stator 41 in order to improve the width that adhesion should preferably enlarge a plurality of adhesion groove 21a; But in order to prevent too much to use adhesive, the cross section that adheres to groove 21a should preferably form the narrow more form of its width of inboard along with more past cylinder 21.As an example; Preferably; Aluminium bar is processed; Cylinder 21 and displacer outer cover 22 become one make 20, three of fixed parts and adhere to groove 21a and can be processed to outer peripheral face at cylinder 21 and be

shape with its cross section and have predetermined distance.

Therefore, if only apply like adhesives such as epoxy resin, then can reduce the use amount of adhesive at a plurality of adhesion groove 21a that are located at cylinder 21.And; If inner stator 41 is clipped in the outer peripheral face of cylinder 21 with can hiding adhesion groove 21a and matches; Then can prevent to be contained in the phenomenon that the adhesive of a plurality of adhesion groove 21a is extruded or leaked between inner stator 41 and cylinder 21; Can improve adhesion property thus, and then can prevent that inner stator 41 breaks away from from cylinder 21, thereby can guarantee operating reliability.

More than, the present invention serves as the basis with embodiments of the invention and accompanying drawing and this is specified the present invention as example.But scope of the present invention is not limited to above embodiment and accompanying drawing, the content of being put down in writing in claims that scope of the present invention is stated after should only being confined to.

Claims

1. a ultra-low temperature refrigerating device is characterized in that, comprising:

Closed shell,

Fixed part is located at the inside of closed shell, and this fixed part comprises cylinder,

Movable member, the displacer of linear reciprocating motion is carried out along the piston that axially carries out linear reciprocating motion with along the direction opposite with piston in the inboard that is included in cylinder,

Permanent magnet, it is connected with piston, and

Inner stator and external stator are set to keep the gap with permanent magnet, by mutual electromagnetic power permanent magnet are back and forth driven;

Inner stator is fixed in the outer peripheral face of cylinder with the mode that can contact, and external stator is fixed in the inner peripheral surface of closed shell with the mode that can contact.

2. ultra-low temperature refrigerating device according to claim 1 is characterized in that,

Comprise leaf spring, this leaf spring resiliency supported displacer;

Leaf spring is fixed in external stator through miscellaneous part.

3. ultra-low temperature refrigerating device according to claim 2 is characterized in that,

Comprise support, an end of this support passes through bolt in the edge of leaf spring;

The other end of support is fixedly welded on external stator.

4. according to each described ultra-low temperature refrigerating device in the claim 1 to 3, it is characterized in that,

Closed shell comprises the package of drum and is fixedly welded on the framework on this package;

External stator is fixedly welded on framework.

5. according to each described ultra-low temperature refrigerating device in the claim 1 to 4, it is characterized in that comprise a plurality of adhesion grooves, said a plurality of adhesion grooves are arranged at the outer peripheral face of cylinder, be used to accommodate inner stator is fixed in the adhesive on the outer peripheral face of cylinder.

6. ultra-low temperature refrigerating device according to claim 5 is characterized in that, adheres to groove and has the ring-type that forms in a circumferential direction along the outer peripheral face of cylinder.

7. according to claim 5 or 6 described ultra-low temperature refrigerating devices, it is characterized in that, a plurality of adhesion grooves cylinder axially on have predetermined distance.

8. according to each described ultra-low temperature refrigerating device in the claim 5 to 7, it is characterized in that each cross section that adheres to groove forms, along with the degree of depth apart from the outer peripheral face of cylinder deepens, its width just narrows down.

9. according to each described ultra-low temperature refrigerating device in the claim 5 to 8, it is characterized in that, only be coated with epoxy resin in the inside that adheres to groove.