EP0286462B1 - Miniature joule-thomson expansion refrigerator, and method of manufacturing it - Google Patents

Miniature joule-thomson expansion refrigerator, and method of manufacturing it Download PDF

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Publication number
EP0286462B1
EP0286462B1 EP19880400485 EP88400485A EP0286462B1 EP 0286462 B1 EP0286462 B1 EP 0286462B1 EP 19880400485 EP19880400485 EP 19880400485 EP 88400485 A EP88400485 A EP 88400485A EP 0286462 B1 EP0286462 B1 EP 0286462B1
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EP
European Patent Office
Prior art keywords
casing
mandrel
tube
tubes
cooler
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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EP19880400485
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German (de)
French (fr)
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EP0286462A1 (en
Inventor
Serge Reale
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LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/02—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point using Joule-Thompson effect; using vortex effect
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00—Making other particular articles
    • B21D53/02—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers
    • B21D53/06—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers of metal tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
    • F28D7/02—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being helically coiled
    • F28D7/024—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being helically coiled the conduits of only one medium being helically coiled tubes, the coils having a cylindrical configuration
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
    • F28D7/04—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being spirally coiled

Definitions

  • the present invention relates to a miniature Joule-Thomson double-coil expansion cooler, of the type described in the preamble to claim 1.
  • Such coolers (see for example FR-A-1468862) ensure a high efficiency of the Joule expansion -Thomson, because the pressure after expansion is low, the pressure losses of the low-pressure circuit being low.
  • the FR-A-1468862 uses elastic shims.
  • the object of the invention is to enable a reduced mass, and therefore thermal inertia, to be achieved at a low cost price.
  • the subject of the invention is a cooler of the aforementioned type, characterized by the content of the characterizing part of claim 1.
  • the Joule-Thomson miniature expansion cooler according to the invention is characterized by the content of the characterizing part of claim 7.
  • the cryostat shown in Figure 1 consists of a Dewar 1, a cooler 2 and a device 3 for supplying the latter with high-pressure gas.
  • the Dewar 1 is a double vacuum envelope delimiting a cylindrical well 4 of axis XX supposed to be vertical, open at its upper end and closed at its lower end by a bottom 5.
  • An element 6 to be refrigerated for example an infrared detector connected by electrical wires (not shown) to the outside of the cryostat, is fixed, in particular glued, to the bottom 5, in the vacuum space.
  • the upper end of the well 4 is connected to the upper wall 7 of the Dewar, which is flat and horizontal.
  • the cooler 2 of generally cylindrical shape with axis XX, consists of an inner tubular mandrel 8, an outer tubular casing 9 surrounding the mandrel 8 over its entire length, a connecting head 10, and two stainless steel capillary tubes, namely an inner tube 11 and an outer tube 12.
  • the head 10 is constituted by a relatively massive ring in the bore of which the upper end of the casing 9 is fitted and fixed by brazing or gluing.
  • a collar 13, fitted into the inlet of the well 4 projects downward around the bore of the ring 10 and around the casing 9.
  • This ring is applied by a flat underside on the wall 7 of the Dewar, the seal being obtained by means of an O-ring 14.
  • Another cylindrical collar 15, having two vertical grooves 16, projects upwards along the outer periphery of the ring 10.
  • a cup 17 is inserted in the collar 15. Its hollow internal part fits into the upper end of the mandrel. the shutter, and its outer, flat collar, is applied to the shoulder formed at the base of the collar 15. This collar has on its periphery a series of lights 18 facing the space separating the mandrel from the envelope 9.
  • the inner tube 11 is wound in a helix over most of the length of the mandrel 8 which emerges from the head 10, from the lower end of this mandrel, and it is fixed by brazing thereon, over its entire length. wound length. From the upper end of this wound part, the tube 11 crosses the mandrel 8 radially with a seal, then extends upwards and crosses the bottom of the cup 17 with a seal, then it passes through a groove 16 and describes a half-loop around the collar 15.
  • the outer tube 12 is wound in a helix over most of the length of the casing 9 which emerges from the head 10, from the lower end of this casing and against the internal wall of the latter, and it is fixed to this wall by brazing along its coiled part. From the upper end of this wound part, the tube 12 extends upwards through a hole 18 in the cup 17, then crosses the other groove 16 horizontally and describes a complete loop around the collar 15.
  • the lower ends of the two tubes 11 and 12 are connected by an elbow 19 pierced with a calibrated expansion orifice 20, which opens facing the bottom 5 of the Dewar.
  • the supply device 3 comprises a capacity 21 of a gas, or of a mixture of gases, under very high pressure, for example under 500 to 700 bars.
  • This capacity is applied to the face 7 of the Dewar and has a large recess 22 of axis XX around the well 4.
  • the wall of the capacity 21 is also pierced an exhaust channel 25 which opens on the one hand into the recess 22, and on the other hand into the open air.
  • the high-pressure gas is conveyed by the tubes 11 and 12 to the orifice 20, expands and rises between the mandrel 8 and the casing 9 while cooling the high-pressure gas. Then the low-pressure gas escapes through the ports 18, the grooves 16 and the channel 25.
  • the vibrations do not affect the cooler or the element to be cooled. It is also noted that the elements 8 and 9 do not undergo significant mechanical forces and can therefore be produced in the form of very thin stainless steel tubes, which reduces the mass, and therefore the thermal inertia, of the cooler. .
  • the tube 11, previously tinned, is wound on the mandrel 8, itself provisionally threaded on a cylindrical core not shown ( Figure 2), and the tube 12, also tinned, is wound on an auxiliary mandrel 26 externally threaded at the desired pitch and made of a non-stick material and resistant to soldering, for example titanium ( Figure 3).
  • the two tubes 11 and 12 are wound in the same direction and with the same pitch.
  • the casing 9 is threaded, without significant play, onto the tube 12 and receives the head 10 (FIG. 4), then the two assemblies 8-11 and 9-10-12-26 thus obtained are passed through a brazing oven ( figure 5).
  • the tubes 11 and 12 are thus secured to the respective elements 8 and 9 which carry them.
  • the auxiliary mandrel 26 is then removed by a unscrewing movement (FIG. 6), then the assembly 8-11 is introduced into the assembly 9-12 by a screwing movement (FIG. 7). Then, after having correctly positioned these two assemblies with respect to each other, both in the radial and in the axial direction, the cup 17 is put in place (FIG. 8), after which the cooler is completed by the fitting the elbow 19 (FIG. 9).
  • the casing 9 can be omitted and the tube 12 brazed directly on the internal wall of the well 4.
  • the use of the casing 9 has the advantage of leading to a completely autonomous cooler with respect to the Dewar and which can easily be put in place removably therein, without contact between the heat exchanger and the Dewar well.
  • the gas used depends on the cooling capacity required and the low temperature that one wants to reach. It can be in particular argon or a mixture of argon with a "Freon", whose boiling point is higher but which has a stronger Joule-Thomson effect.
  • the elbow 19 can be omitted and a detent orifice is placed at the lower end of each tube 11, 12. In this case, it is possible to supply the two tubes with two different gases.
  • the casing 9 and the mandrel 8 can themselves be conical and, ultimately, flat.
  • FIG. 10 a particular embodiment of the invention in which the cooler 2A consists of two parallel discs 8A and 9A, kept at a distance from each other by a ring 17A with lights 18A, with a capillary tube 11A in the form of a flat spiral brazed on the inner face of the disc 8A and a capillary tube 12A in the form of a flat spiral nested in the first spiral, brazed on the disc 9A.
  • Each tube 11A, 12A ends at the center of the device with a calibrated expansion orifice oriented towards the element 6 to be cooled.
  • each disc may include a peripheral rim 8B, 9B on which a circular cover 27 is fixed, so as to delimit two vacuum chambers.
  • the element 6 to be cooled is bonded to the disk 8A in the adjacent vacuum chamber, which completes the cryostat.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Description

La présente invention est relative à un refroidisseur miniature à détente Joule-Thomson à double bobinage, du type décrit dans le préambule de la revendication 1. De tels refroidisseurs (voir par exemple FR-A-1468862) assurent une efficacité élevée de la détente Joule-Thomson, car la pression après détente est basse, les pertes de charge du circuit basse-pression étant faibles.The present invention relates to a miniature Joule-Thomson double-coil expansion cooler, of the type described in the preamble to claim 1. Such coolers (see for example FR-A-1468862) ensure a high efficiency of the Joule expansion -Thomson, because the pressure after expansion is low, the pressure losses of the low-pressure circuit being low.

Dans ces refroidisseurs, il est nécessaire qu'une bonne étanchéité soit obtenue entre d'une part le tube intérieur et le mandrin, d'autre part le tube extérieur et l'enveloppe, pour éviter que le gaz froid basse-pression by-passe les tubes, lesquels véhiculent le gaz haute-pression destiné à être détendu.In these coolers, it is necessary that a good seal is obtained between on the one hand the inner tube and the mandrel, on the other hand the outer tube and the casing, to prevent the cold low-pressure gas by-passing the tubes, which convey the high-pressure gas intended to be expanded.

Pour obtenir ce résultat, le FR-A-1468862 utilise des cales élastiques. Or, pour obtenir une vitesse de mise en froid élevée, il faut réduire autant que possible l'inertie thermique, et donc la masse, du refroidisseur, alors que lesdites cales, en imposant des contraintes mécaniques radiales relativement élevées au mandrin et à l'enveloppe, obligent à augmenter l'épaisseur et donc la masse de ces éléments.To obtain this result, the FR-A-1468862 uses elastic shims. However, to obtain a high cooling rate, it is necessary to reduce as much as possible the thermal inertia, and therefore the mass, of the cooler, while said shims, by imposing relatively high radial mechanical stresses on the mandrel and the envelope, require to increase the thickness and therefore the mass of these elements.

L'invention a pour but de permettre d'atteindre à un faible prix de revient une masse, et donc une inertie thermique, réduites.The object of the invention is to enable a reduced mass, and therefore thermal inertia, to be achieved at a low cost price.

A cet effet, l'invention a pour objet un refroidisseur du type précité, caractérisé par le contenu de la partie caractérisante de la revendication 1.To this end, the subject of the invention is a cooler of the aforementioned type, characterized by the content of the characterizing part of claim 1.

L'invention a également pour objet un procédé de fabrication d'un tel refroidisseur. Suivant ce procédé:

  • ― on bobine le tube intérieur sur le mandrin, et on le fixe sur celui-ci;
  • ― on bobine le tube extérieur contre la paroi interne de l'enveloppe, et on le fixe contre cette paroi; et
  • ― on insère le mandrin dans l'enveloppe par un mouvement de vissage.
The invention also relates to a method of manufacturing such a cooler. According to this process:
  • - The inner tube is wound on the mandrel, and fixed on it;
  • - The outer tube is wound against the inner wall of the envelope, and it is fixed against this wall; and
  • - the mandrel is inserted into the envelope by a screwing movement.

Suivant un autre mode de réalisation, présentant des avantages analogues, le refroidisseur miniature à détente Joule-Thomson suivant l'invention, du type décrit dans le préambule de la revendication 7 (GB-A-1168997), est caractérisé par le contenu de la partie caractérisante de la revendication 7.According to another embodiment, presenting similar advantages, the Joule-Thomson miniature expansion cooler according to the invention, of the type described in the preamble of claim 7 (GB-A-1168997), is characterized by the content of the characterizing part of claim 7.

Deux exemples de réalisation de l'invention vont maintenant être décrit en regard des dessins annexés, sur lesquels:

  • ― la figure 1 est une vue partielle en coupe longitudinale d'un cryostat muni d'un refroidisseur conforme à l'invention;
  • ― les figures 2 à 9 illustrent schématiquement les étapes successives de fabrication du refroidisseur de la figure 1; et
  • ― la figure 10 représente en coupe axiale un autre mode de réalisation de l'invention.
Two embodiments of the invention will now be described with reference to the appended drawings, in which:
  • - Figure 1 is a partial view in longitudinal section of a cryostat provided with a cooler according to the invention;
  • - Figures 2 to 9 schematically illustrate the successive stages of manufacture of the cooler of Figure 1; and
  • - Figure 10 shows in axial section another embodiment of the invention.

Le cryostat représenté à la figure 1 est constitué d'un Dewar 1, d'un refroidisseur 2 et d'un dispositif 3 d'alimentation de ce dernier en gaz haute-pression.The cryostat shown in Figure 1 consists of a Dewar 1, a cooler 2 and a device 3 for supplying the latter with high-pressure gas.

Le Dewar 1 est une double enveloppe sous vide délimitant un puits cylindrique 4 d'axe X-X supposé vertical, ouvert à son extrémité supérieure et fermé à son extrémité inférieure par un fond 5. Un élément 6 à réfrigérer, par exemple un détecteur infra-rouge relié par des fils électriques (non représentés) à l'extérieur du cryostat, est fixé, notamment collé, sur le fond 5, dans l'espace sous vide. L'extrémité supérieure du puits 4 est reliée à la paroi supérieure 7 du Dewar, qui est plane et horizontale.The Dewar 1 is a double vacuum envelope delimiting a cylindrical well 4 of axis XX supposed to be vertical, open at its upper end and closed at its lower end by a bottom 5. An element 6 to be refrigerated, for example an infrared detector connected by electrical wires (not shown) to the outside of the cryostat, is fixed, in particular glued, to the bottom 5, in the vacuum space. The upper end of the well 4 is connected to the upper wall 7 of the Dewar, which is flat and horizontal.

Le refroidisseur 2, de forme générale cylindrique d'axe X-X, se compose d'un mandrin tubulaire intérieur 8, d'une enveloppe extérieure tubulaire 9 entourant le mandrin 8 sur toute sa longueur, d'une tête de liaison 10, et de deux tubes capillaires en acier inoxydable, à savoir un tube intérieur 11 et un tube extérieur 12.The cooler 2, of generally cylindrical shape with axis XX, consists of an inner tubular mandrel 8, an outer tubular casing 9 surrounding the mandrel 8 over its entire length, a connecting head 10, and two stainless steel capillary tubes, namely an inner tube 11 and an outer tube 12.

La tête 10 est constituée par une bague relativement massive dans l'alésage de laquelle l'extrémité supérieure de l'enveloppe 9 est emboîtée et fixée par brasage ou collage. Un collet 13, emboîté dans l'entrée du puits 4, fait saillie vers le bas autour de l'alésage de la bague 10 et autour de l'enveloppe 9. Cette bague s'applique par une face inférieure plane sur la paroi 7 du Dewar, l'étanchéïté étant obtenue au moyen d'un joint torique 14. Un autre collet cylindrique 15, présentant deux rainures verticales 16, fait saillie vers le haut le long de la périphérie extérieure de la bague 10.The head 10 is constituted by a relatively massive ring in the bore of which the upper end of the casing 9 is fitted and fixed by brazing or gluing. A collar 13, fitted into the inlet of the well 4, projects downward around the bore of the ring 10 and around the casing 9. This ring is applied by a flat underside on the wall 7 of the Dewar, the seal being obtained by means of an O-ring 14. Another cylindrical collar 15, having two vertical grooves 16, projects upwards along the outer periphery of the ring 10.

Une coupelle 17 est insérée dans le collet 15. Sa partie intérieure, en creux, s'emboîte dans l'extrémité supérieure du mandrin en l'obturant, et sa collerette extérieure, plane, s'applique sur l'épaulement formé à la base du collet 15. Cette collerette présente sur son pourtour une série de lumières 18 en regard de l'espace séparant le mandrin de l'enveloppe 9.A cup 17 is inserted in the collar 15. Its hollow internal part fits into the upper end of the mandrel. the shutter, and its outer, flat collar, is applied to the shoulder formed at the base of the collar 15. This collar has on its periphery a series of lights 18 facing the space separating the mandrel from the envelope 9.

Le tube intérieur 11 est bobiné en hélice sur l'essentiel de la longueur du mandrin 8 qui émerge de la tête 10, à partir de l'extrémité inférieure de ce mandrin, et il est fixé par brasage sur celui-ci, sur toute sa longueur bobinée. A partir de l'extrémité supérieure de cette partie bobinée, le tube 11 traverse radialement à joint étanche le mandrin 8 puis s'étend vers le haut et traverse à joint étanche le fond de la coupelle 17, puis il traverse une rainure 16 et décrit une demi-boucle autour du collet 15.The inner tube 11 is wound in a helix over most of the length of the mandrel 8 which emerges from the head 10, from the lower end of this mandrel, and it is fixed by brazing thereon, over its entire length. wound length. From the upper end of this wound part, the tube 11 crosses the mandrel 8 radially with a seal, then extends upwards and crosses the bottom of the cup 17 with a seal, then it passes through a groove 16 and describes a half-loop around the collar 15.

De même, le tube extérieur 12 est bobiné en hélice sur l'essentiel de la longueur de l'enveloppe 9 qui émerge de la tête 10, à partir de l'extrémité inférieure de cette enveloppe et contre la paroi interne de celle-ci, et il est fixé à cette paroi par brasage tout le long de sa partie bobinée. A partir de l'extrémité supérieure de cette partie bobinée, le tube 12 s'étend vers le haut en traversant une lumière 18 de la coupelle 17, puis traverse horizontalement l'autre rainure 16 et décrit une boucle complète autour du collet 15.Likewise, the outer tube 12 is wound in a helix over most of the length of the casing 9 which emerges from the head 10, from the lower end of this casing and against the internal wall of the latter, and it is fixed to this wall by brazing along its coiled part. From the upper end of this wound part, the tube 12 extends upwards through a hole 18 in the cup 17, then crosses the other groove 16 horizontally and describes a complete loop around the collar 15.

Les extrémités inférieures des deux tubes 11 et 12 sont reliées par un coude 19 percé d'un orifice de détente calibré 20, lequel débouche en regard du fond 5 du Dewar.The lower ends of the two tubes 11 and 12 are connected by an elbow 19 pierced with a calibrated expansion orifice 20, which opens facing the bottom 5 of the Dewar.

Le dispositif d'alimentation 3 comprend une capacité 21 d'un gaz, ou d'un mélange de gaz, sous très haute pression, par exemple sous 500 à 700 bars. Cette capacité s'applique sur la face 7 du Dewar et présente un large évidement 22 d'axe X-X autour du puits 4. Un contre-alésage 23, dans lequel est emboîtée et brasée la partie supérieure du collet 15, est prévu dans la région de l'axe X-X. Dans l'évidement 22 débouche un organe de sortie 24 d'une vanne d'alimentation commandée à distance, et les extrémités amont des tubes 11 et 12 pénètrent à joint étanche dans cet organe 24. La paroi de la capacité 21 est par ailleurs percée d'un canal d'échappement 25 qui débouche d'une part dans l'évidement 22, et d'autre part à l'air libre.The supply device 3 comprises a capacity 21 of a gas, or of a mixture of gases, under very high pressure, for example under 500 to 700 bars. This capacity is applied to the face 7 of the Dewar and has a large recess 22 of axis XX around the well 4. A counterbore 23, in which the upper part of the collar 15 is fitted and brazed, is provided in the region of axis XX. In the recess 22 there opens an outlet member 24 of a remotely controlled supply valve, and the upstream ends of the tubes 11 and 12 penetrate with a seal in this member 24. The wall of the capacity 21 is also pierced an exhaust channel 25 which opens on the one hand into the recess 22, and on the other hand into the open air.

En fonctionnement, le gaz haute-pression est véhiculé par les tubes 11 et 12 jusqu'à l'orifice 20, se détend et remonte entre le mandrin 8 et l'enveloppe 9 en refroidissant le gaz haute-pression. Puis le gaz basse-pression s'échappe par les lumières 18, les rainures 16 et le canal 25.In operation, the high-pressure gas is conveyed by the tubes 11 and 12 to the orifice 20, expands and rises between the mandrel 8 and the casing 9 while cooling the high-pressure gas. Then the low-pressure gas escapes through the ports 18, the grooves 16 and the channel 25.

Grâce au brasage indépendant des deux tubes, on obtient un refroidisseur ayant à la fois une très bonne efficacité d'échange thermique au niveau des tubes 11 et 12, car il n'y a pratiquement pas de fuites entre ces tubes et les éléments associés 8 et 9, et une faible perte de charge dans le circuit basse-pression. A son tour, cette faible perte de charge permet d'utiliser des débits de gaz accrus et donc d'obtenir des puissances frigorifiques relativement importantes.Thanks to the independent brazing of the two tubes, a cooler is obtained which has very good heat exchange efficiency at the level of the tubes 11 and 12, since there is practically no leakage between these tubes and the associated elements 8 and 9, and a low pressure drop in the low-pressure circuit. In turn, this low pressure drop makes it possible to use increased gas flow rates and therefore to obtain relatively high cooling capacities.

De plus, grâce à la présence de jeux radiaux importants, les vibrations n'affectent ni le refroidisseur ni l'élément à refroidir. On remarque également que les éléments 8 et 9 ne subissent pas d'efforts mécaniques importants et peuvent donc être réalisés sous la forme de tubes en acier inoxydable de très faible épaisseur, ce qui réduit la masse, et donc l'inertie thermique, du refroidisseur.In addition, thanks to the presence of large radial clearances, the vibrations do not affect the cooler or the element to be cooled. It is also noted that the elements 8 and 9 do not undergo significant mechanical forces and can therefore be produced in the form of very thin stainless steel tubes, which reduces the mass, and therefore the thermal inertia, of the cooler. .

La simplicité de la fabrication du refroidisseur 2, qui conduit à un faible prix de revient, apparaîtra en considérant la succession d'opérations illustrée aux figures 2 à 9.The simplicity of manufacturing the cooler 2, which leads to a low cost price, will appear by considering the succession of operations illustrated in FIGS. 2 to 9.

Le tube 11, préalablement étamé, est bobiné sur le mandrin 8, lui-même enfilé provisoirement sur un noyau cylindrique non représenté (figure 2), et le tube 12, également étamé, est bobiné sur un mandrin auxiliaire 26 extérieurement fileté au pas désiré et constitué d'une matière anti-adhérente et résistante vis-à-vis du brasage, par exemple de titane (figure 3). Les deux tubes 11 et 12 sont bobinés dans le même sens et avec le même pas.The tube 11, previously tinned, is wound on the mandrel 8, itself provisionally threaded on a cylindrical core not shown (Figure 2), and the tube 12, also tinned, is wound on an auxiliary mandrel 26 externally threaded at the desired pitch and made of a non-stick material and resistant to soldering, for example titanium (Figure 3). The two tubes 11 and 12 are wound in the same direction and with the same pitch.

L'enveloppe 9 est enfilée, sans jeu notable, sur le tube 12 et reçoit la tête 10 (figure 4), puis les deux ensembles 8-11 et 9-10-12-26 ainsi obtenus sont passés dans un four de brasage (figure 5). Les tubes 11 et 12 sont ainsi solidarisés avec les éléments respectifs 8 et 9 qui les portent.The casing 9 is threaded, without significant play, onto the tube 12 and receives the head 10 (FIG. 4), then the two assemblies 8-11 and 9-10-12-26 thus obtained are passed through a brazing oven ( figure 5). The tubes 11 and 12 are thus secured to the respective elements 8 and 9 which carry them.

On retire ensuite le mandrin auxiliaire 26, par un mouvement de dévissage (figure 6), puis on introduit l'ensemble 8-11 dans l'ensemble 9-12 par un mouvement de vissage (figure 7). Puis, après avoir correctement positionné ces deux ensembles l'un par rapport à l'autre, tant dans le sens radial que dans le sens axial, on met en place la coupelle 17 (figure 8), après quoi on complète le refroidisseur par la mise en place du coude 19 (figure 9).The auxiliary mandrel 26 is then removed by a unscrewing movement (FIG. 6), then the assembly 8-11 is introduced into the assembly 9-12 by a screwing movement (FIG. 7). Then, after having correctly positioned these two assemblies with respect to each other, both in the radial and in the axial direction, the cup 17 is put in place (FIG. 8), after which the cooler is completed by the fitting the elbow 19 (FIG. 9).

En variante, l'enveloppe 9 peut être supprimée et le tube 12 brasé directement sur la paroi interne du puits 4. Cependant, l'utilisation de l'enveloppe 9 présente l'avantage de conduire à un refroidisseur entièrement autonome par rapport au Dewar et que l'on peut sans difficulté mettre en place de façon amovible dans celui-ci, sans contact entre l'échangeur de chaleur et le puits du Dewar.As a variant, the casing 9 can be omitted and the tube 12 brazed directly on the internal wall of the well 4. However, the use of the casing 9 has the advantage of leading to a completely autonomous cooler with respect to the Dewar and which can easily be put in place removably therein, without contact between the heat exchanger and the Dewar well.

Le gaz utilisé dépend de la puissance frigorifique nécessaire et de la température basse que l'on veut atteindre. Ce peut être notamment de l'argon ou un mélange d'argon avec un "Fréon", dont le point d'ébullition est plus élevé mais qui possède un effet Joule-Thomson plus fort.The gas used depends on the cooling capacity required and the low temperature that one wants to reach. It can be in particular argon or a mixture of argon with a "Freon", whose boiling point is higher but which has a stronger Joule-Thomson effect.

En variante encore, on peut supprimer le coude 19 et disposer un orifice de détente à l'extrémité inférieure de chaque tube 11, 12. Dans ce cas, il est possible d'alimenter les deux tubes avec deux gaz différents.As a further variant, the elbow 19 can be omitted and a detent orifice is placed at the lower end of each tube 11, 12. In this case, it is possible to supply the two tubes with two different gases.

Il est à noter que comme l'enveloppe 9 n'est pas en contact avec le puits 4, on peut envisager d'introduire le même refroidisseur 2 dans un puits de Dewar de forme non cylindrique, notamment conique.It should be noted that since the casing 9 is not in contact with the well 4, it is possible to envisage introducing the same cooler 2 into a Dewar well of non-cylindrical shape, in particular conical.

De plus, l'enveloppe 9 et le mandrin 8 peuvent eux-mêmes être coniques et, à la limite, plats. On aboutit alors à un mode de réalisation particulier de l'invention (Figure 10) dans lequel le refroidisseur 2A est constitué de deux disques parallèles 8A et 9A, maintenus à distance l'un de l'autre par une bague 17A à lumières 18A, avec un tube capillaire 11A en forme de spirale plane brasé sur la face intérieure du disque 8A et un tube capillaire 12A en forme de spirale plane imbriquée dans la première spirale, brasé sur le disque 9A. Chaque tube 11A, 12A se termine au centre du dispositif par un orifice calibré de détente orienté vers l'élément 6 à refroidir.In addition, the casing 9 and the mandrel 8 can themselves be conical and, ultimately, flat. This then leads to a particular embodiment of the invention (FIG. 10) in which the cooler 2A consists of two parallel discs 8A and 9A, kept at a distance from each other by a ring 17A with lights 18A, with a capillary tube 11A in the form of a flat spiral brazed on the inner face of the disc 8A and a capillary tube 12A in the form of a flat spiral nested in the first spiral, brazed on the disc 9A. Each tube 11A, 12A ends at the center of the device with a calibrated expansion orifice oriented towards the element 6 to be cooled.

En particulier, comme représenté, chaque disque peut comporter un rebord périphérique 8B, 9B sur lequel est fixé un couvercle circulaire 27, de façon à délimiter deux chambres sous vide. L'élément 6 à refroidir est collé sur le disque 8A dans la chambre sous vide adjacente, ce qui complète le cryostat.In particular, as shown, each disc may include a peripheral rim 8B, 9B on which a circular cover 27 is fixed, so as to delimit two vacuum chambers. The element 6 to be cooled is bonded to the disk 8A in the adjacent vacuum chamber, which completes the cryostat.

Claims (10)

1. Miniature Joule-Thomson expansion cooler (2) of the type comprising a mandrel (8) generated by revolution and surrounded by a casing (9) having the same axis, and two tubes (11, 12) spirally wound in the space located between the mandrel and the casing, of which tubes an inner tube (11) is in contact with the mandrel and an outer tube (12) is in contact with the casing, the inner diameter of the spiral formed by the external tube being less than the outer diameter of the spiral formed by the inner tube, the distance between the mandrel and the casing being greater than the diameter of the tubes, and the turns of the two tubes overlapping one inside the other, characterised in that the inner tube (11) is attached, in particular by soldering, to the mandrel (8) over its entire wound length, while the outer tube (12) is attached, in particular by soldering, independently of the inner tube, to the inner wall of the casing (9), over its entire wound length.
2. Cooler according to claim 1, characterised in that the mandrel (8) and the casing (9) are connected at their upstream ends by a head (10), so that a self-contained assembly is formed.
3. Cooler according to claim 1, characterised in that the casing is formed by the inner wall of a well (4) which is part of a Dewar flask.
4. Cooler according to any one of claims 1 to 3, characterised in that the downstream ends of the two tubes (11, 12) are joined by a connecting element (19) provided with an expansion hole (20).
5. Cooler according to any one of claims 1 to 4, characterised in that the mandrel (8) and the casing (9) are cylindrical.
6. Cooler according to any one of claims 1 to 5, characterised in that the mandrel (8) and the casing (9) are conical.
7. Miniature Joule-Thomson expansion cooler (2A) of the type comprising a flat casing containing a spirally wound winding, the flat casing itself comprising two parallel surfaces (8A, 9A), and means (17A) for keeping these surfaces at a distance from each other, characterised in that the winding comprises a spiral tube (11A, 12A) attached, in particular by soldering, to each surface, the turns of the two tubes being interpenetrating, with each tube emerging in the region of the centre of the spiral through an expansion hole, and the distance between the two surfaces being greater than the diameter of the tubes.
8. Manufacturing process for a cooler (2) according to claim 1, characterised in that:
― the inner tube (11) is wound on the mandrel (8), and is attached to this mandrel;
― the outer tube (12) is wound against the inner wall of the casing (9), and is attached against this wall; and
― the mandrel (8) is inserted into the casing (9) by a screwing movement.
9. Process according to claim 8, characterised in that, in order to position the outer tube (12) within the casing (9), this tube is wound on an additional, preferably threaded mandrel (26), and the assembly is introduced into the casing (9) without an appreciable amount of clearance.
10. Process according to one of claims 8 and 9, characterised in that the two tubes (11, 12) are tin-plated beforehand, and are attached by soldering to the mandrel (8) and against the casing (9), respectively.
EP19880400485 1987-03-06 1988-03-02 Miniature joule-thomson expansion refrigerator, and method of manufacturing it Expired - Lifetime EP0286462B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8703027A FR2611870B1 (en) 1987-03-06 1987-03-06 MINIATURE JOULE-THOMSON EXPANSION COOLER AND MANUFACTURING METHOD THEREOF
FR8703027 1987-03-06

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EP0286462A1 EP0286462A1 (en) 1988-10-12
EP0286462B1 true EP0286462B1 (en) 1991-09-18

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EP19880400485 Expired - Lifetime EP0286462B1 (en) 1987-03-06 1988-03-02 Miniature joule-thomson expansion refrigerator, and method of manufacturing it

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DE (1) DE3864878D1 (en)
FR (1) FR2611870B1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2665237B1 (en) * 1990-07-27 1992-11-13 Coflexip FLEXIBLE TUBULAR CARCASS AND CONDUIT COMPRISING SUCH A CARCASS.
FR2749651B1 (en) * 1996-06-06 1998-08-28 Framatome Sa PROTECTION DEVICE FOR AN INSPECTION OR CONTROL DEVICE USED IN A HIGH TEMPERATURE ENVIRONMENT AND ITS USE
FR2782785B1 (en) * 1998-08-27 2001-01-19 Air Liquide JOULE-THOMSON COOLER

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1267447A (en) * 1960-09-12 1961-07-21 Philco Corp Cryogenic refrigeration device
US3273356A (en) * 1964-09-28 1966-09-20 Little Inc A Heat exchanger-expander adapted to deliver refrigeration
GB1149962A (en) * 1965-07-30 1969-04-23 British Oxygen Co Ltd Gas liquefier
FR1468862A (en) * 1965-10-21 1967-02-10 Air Liquide Miniature refrigerator; especially for quantum detector
GB1168997A (en) * 1965-12-08 1969-10-29 Emi Ltd Improvements relating to Cooling Apparatus
NO119537B (en) * 1967-04-14 1970-06-01 Hymatic Eng Co Ltd
FR2155770A1 (en) * 1971-10-04 1973-05-25 Ind Chauffage Spiral tube heat exchanger - with tubes contacting shell to define shell-side flow
DE7615571U1 (en) * 1976-05-15 1976-10-07 K. & H. Eppensteiner Gmbh & Co Kg, 6834 Ketsch Built-in liquid filter
DE3038718A1 (en) * 1980-10-14 1982-05-27 Tremonia Prägeerzeugnisse Vertriebs GmbH, 4600 Dortmund Boiler flue gases heat recovery equipment - comprises pipe in path of gas cooled by heated water
EP0128196A4 (en) * 1982-12-01 1985-06-26 William A Little Fast cooldown miniature refrigerators.

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FR2611870A1 (en) 1988-09-09
EP0286462A1 (en) 1988-10-12
DE3864878D1 (en) 1991-10-24
FR2611870B1 (en) 1989-06-09

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