(19)
(11)EP 3 055 636 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
24.07.2019 Bulletin 2019/30

(21)Application number: 14781536.9

(22)Date of filing:  07.10.2014
(51)International Patent Classification (IPC): 
F28F 1/42(2006.01)
F28F 1/40(2006.01)
F28D 21/00(2006.01)
F28D 1/047(2006.01)
F28F 1/32(2006.01)
(86)International application number:
PCT/EP2014/071446
(87)International publication number:
WO 2015/052188 (16.04.2015 Gazette  2015/15)

(54)

METHOD FOR MAKING AN ICE MAKING MACHINE

VERFAHREN ZUR HERSTELLUNG EINER EISMASCHINE

MÉTHODE POUR CONSTRUIRE UNE MACHINE DE FABRICATION DE GLAÇONS


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 11.10.2013 IT MI20131684

(43)Date of publication of application:
17.08.2016 Bulletin 2016/33

(73)Proprietor: Scotsman Ice S.r.L.
20010 Pogliano Milanese (MI) (IT)

(72)Inventor:
  • ROMAGNOLI, Guido
    I-20162 Milano (IT)

(74)Representative: Rapisardi, Mariacristina et al
Ufficio Brevetti Rapisardi S.r.l. Via Serbelloni, 12
20122 Milano
20122 Milano (IT)


(56)References cited: : 
EP-A1- 1 818 641
EP-A1- 2 525 181
JP-A- 2004 279 025
US-A- 4 720 902
US-A- 5 564 184
EP-A1- 2 213 953
JP-A- 2001 248 992
US-A- 3 830 087
US-A- 4 847 989
US-B2- 7 406 838
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to a method for making an ice making machine comprising a condenser for condensation of a coolant fluid based on a hydrocarbon.

    [0002] The use of coolant fluids based on hydrocarbons such as propane in the cooling circuit of ice making machines is known, due to their high performance and their low environmental impact.

    [0003] Said coolant fluids are often used in place of other types of coolant fluid, such as hydrofluorocarbons, chlorofluorocarbons or hydrochlorofluorocarbons which have a decidedly worse environmental impact.

    [0004] However, hydrocarbons also have a criticality linked with the fact of being extremely inflammable or explosive if exposed to sources of heat, flames or fumes, especially in enclosed and under-ventilated environments.

    [0005] In order to limit the dangerousness of hydrocarbons, several specific regulations have been passed which provide for their use in limited quantities, below pre-established thresholds.

    [0006] The sector of condensers for ice making machines has therefore recently been focusing on the search for construction solutions involving the use of hydrocarbons, but in the quantities allowed by the various safety regulations.

    [0007] WO2013/106725 illustrates a condenser comprising two manifolds, flat connection tubes between the manifolds, and a pack of fins fixed between the flat sides of the tubes. In order to contain the inner volume of the condenser, the two manifolds have specific proportioning, and the flat tubes have a plurality of inner micro-channels alongside each other. One of the drawbacks of this type of condenser consists in the fact that the side zones facing between the micro-channels cannot be used for thermal exchange and do not contribute to improving efficiency of the condenser.

    [0008] Documents EP2525181A1, US4847989A, EP1818641A1 and US7406838B2 also disclose such condensers or ice making machines.

    [0009] The technical task of the present invention is, therefore, to provide a method for making an ice making machine which eliminates the above-described technical drawbacks of the prior art.

    [0010] In said technical task, one object of the invention is to provide a method for making an ice making machine comprising a condenser for condensation of a coolant fluid based on a hydrocarbon which has an optimised efficiency, maintaining an extremely reduced inner volume.

    [0011] Not least, an object of the invention is to provide a method for making an ice making machine comprising a simple and inexpensive condenser in its production process.

    [0012] The technical task, and also this and other objects, according to the present invention, are obtained by providing a method for making an ice making machine according to claim 1.

    [0013] The method for making the condenser provides for a step of coupling the tubes in the holes of the fins of the fin pack, and the inner micro-grooves of the tubes are made without removal of material.

    [0014] The micro-grooves are made by crushing of the thickness of the tubes performed along lines of the inner surface of the tubes.

    [0015] The advantages deriving from the method for making an ice making machine according to the invention are numerous.

    [0016] Whereas in traditional condenser tubes of the same type having a smooth inner wall, there is a layer of laminar flow adjacent to the inner wall of the tubes which creates a barrier to heat transfer, in the tubes of a condenser according to the invention, the micro-grooves prevent the formation of the layer of laminar flow and therefore guarantee the creation of a turbulent flow on the entire inner section of the tubes, thus considerably improving the efficiency of thermal exchange.

    [0017] For this reason as well, tubes of reduced diameter may be used, which allow many more options for the air circuits which are created around the tubes.

    [0018] A condenser having internally grooved tubes with a reduced diameter allows, with the same performance a reduction of the inner volume of the condenser, with the same exchange surface an increase in performance, and, with the same volume an increase in performance.

    [0019] Other characteristics of the present invention are also defined in the claims which follow.

    [0020] Further characteristics and advantages of the invention will more fully emerge from the description of a preferred but not exclusive embodiment of the method for making an ice making machine according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

    Fig. 1a shows a perspective view of the condenser resulting from the method of the invention;

    Fig. 1b shows a raised side view of the condenser of Fig. 1a;

    Fig. 1c shows a rear view of the condenser of Fig. 1a;

    Fig. 2 shows in detail a portion of the fin pack of the condenser of Fig. 1a with the tubes arranged across it, without the curved ends of coupling between the tubes, in order to appreciate the design of the inner surface of said tubes;

    Fig. 2a shows an enlarged detail of the coupling of a tube in a hole of the fins of the fin pack of Fig. 2;

    Fig. 3 shows a transversal section of a tube of the condenser of Fig. 1a;

    Fig. 4 shows a longitudinal section of a tube of the condenser of Fig. 1a; and

    Fig. 5 shows the tool in the sequence of steps with which the micro-grooves of the tube are made.



    [0021] With reference to the above mentioned figures, a condenser of an ice making machine is shown, denoted in its entirety by reference number 1.

    [0022] In particular, reference will be made to a condenser for the condensation of a coolant fluid based on a hydrocarbon, preferably propane.

    [0023] The ice making machine (not shown) has a coolant circuit of the known type, which comprises, in addition to said condenser 1, also an evaporator on the surface of which the ice forms, a lamination valve and a compressor.

    [0024] The condenser 1 comprises a box-shaped support frame 2, in particular parallelepiped, in which is housed a fin pack 3 and a plurality of tubes 4 fixed in through holes 5 of the fins 3.

    [0025] The tubes 4 have, as illustrated, a circular section and a straight longitudinal axis L.

    [0026] The tubes 4 are arranged parallel to each other and with the longitudinal axis L horizontal and perpendicular with two flat side faces 2a, 2a vertical and opposite the frame 2.

    [0027] The flat side faces 2a, 2a of the frame 2 in turn have support through holes of the tubes 4 from which the ends of said tubes 4 exit.

    [0028] The tubes 4 are arranged in groups, in each of which the tubes 4 are connected in series, at the outer side of the flat side faces 2a, 2a of the frame 2, by means of special 180° connectors 10, 10', so as to form coils which are supplied in parallel with the coolant fluid.

    [0029] The tubes 4 are also arranged in one or more rows of tubes 4, that are on one or more flanked parallel vertical planes.

    [0030] Other connectors 10 connect the tubes 4 belonging to the same row of tubes 4, other connectors 10' connect the tubes 4 belonging to adjacent rows of tubes 4.

    [0031] Obviously, the shape of the coils may be customised as desired by means of special arrangements of the connectors 10, 10' for connection between the tubes 4 of the same row or different rows.

    [0032] The ends of the coils for entry of the coolant fluid are connected to each other by a special inlet manifold 7, and, similarly, the ends of the coils for exit of the coolant fluid are connected to each other by a special outlet manifold 8.

    [0033] The inlet manifold 7 and the outlet manifold 8 are in this case positioned on the outer side of a same flat side face 2a of the frame 2, but could be positioned on the outer side of different faces of the frame 2.

    [0034] The fins 3 have a same substantially quadrangular flat shape and are aligned parallel to each other along an alignment axis oriented in the direction of the longitudinal axis L of the tubes 4.

    [0035] The fins 3 also have longitudinal slits 6 which penetrate for the entire thickness of the fins 3, creating passages for air also in the direction of the alignment axis of the fins 3.

    [0036] In other embodiments, the slits of the fins 3 may not be provided.

    [0037] The fins 3 and the tubes 4 are made of different thermally conductive material: for example, it is possible to provide fins 3 in aluminium and tubes 4 in copper.

    [0038] The tubes 4 have micro-grooves 9 on their inner surface.

    [0039] The micro-grooves 9 are configured and arranged so that the inner surface of the tubes 4 is greater than their outer surface.

    [0040] The micro-grooves 9 extend along spiral lines which wind around the axis L of the tubes 4 for the entire longitudinal extension of the tubes 4.

    [0041] The tubes 4 have a minimum inner thickness "d" between 0.1 mm and 0.3 mm at the bottom 9a of the micro-grooves 9, a maximum inner thickness "D" between 0.15 mm and 0.6 mm at the top 9b of the micro-grooves 9, and an outer diameter Φ comprised between 4 mm and 12 mm.

    [0042] The micro-grooves 9 also extend parallel to each other with a spacing step not exceeding 1 mm.

    [0043] The increase in the exchange surface determined by the micro-grooves 9 allows tubes 4 with a limited diameter to be obtained and a total inner volume of the tubes such as to house no more than 150 grams of coolant fluid, in accordance with the strictest safety requirements, maintaining optimal performance for the condenser 1.

    [0044] Advantageously, the micro-grooves 9 of the tubes 4 are made without removal of material, in order not to weaken the structure and penalise functioning of the tubes 4.

    [0045] The micro-grooves 9 are therefore made by crushing of the thickness of the tubes 4 performed along specific lines of the inner surface of the tubes 4, for example as described above along helicoidal lines which wind around the longitudinal axis L of the tubes 4.

    [0046] The micro-grooves 9 are advantageously made, after coupling the tubes 4 in the holes 5 of the fins 3 of the fin pack, by means of a radial force applied from inside the tubes 4 and at least sufficient to create the micro-grooves 9 together with a slight radial expansion of the tubes 4 which consolidates coupling of the tubes 4 into the holes 5 of the fins 3 of the fin pack.

    [0047] In practice, for making of the micro-grooves 9, a tool 11 is used having a stem 12 which ends with a tapered work head 13, and a coaxial gripper 15 external to the stem 12 and provided with radially retractable grip sectors 15a.

    [0048] After fitting the fins 3 onto the tubes 4, the tubes 4 are blocked in position by means of a blocking device 14 which tightens the connectors 10, 10'.

    [0049] Initially, the work head 13 of the tool 11 is pointed against an end of a tube 4 and the gripper 15 translates axially until it surmounts the end of the tube 4.

    [0050] Subsequently, the gripper 15 tightens on the tube 4 causing its sectors 15a to retract radially.

    [0051] With the gripper 15 tightened on the tube 4, the stem 12 translates axially in the direction of introduction into the tube 4 and the stem 12 rotates in a synchronised way on its own axis.

    [0052] The work head 13 has a perimeter corner of moulding 13a which engages against the inner surface of the tube 4, exerting a crushing force of the thickness of the tube 4.

    [0053] The roto-translational movement of the tool continues along the entire longitudinal extension of the tube 4 for completion of the helicoidal micro-grooves 9.

    [0054] The crushing force of the thickness of the tube 4 from inside is at least sufficient also to expand radially the section of the tubes 4.

    [0055] This slight radial expansion of the tubes 4 produces, at the holes 5, a plastic deformation 5' of the wall of the holes 5, with which the holes 5 tighten more firmly on the tube 4.

    [0056] The method for making an ice making machine as conceived herein is susceptible to many modifications and variations, all falling within the scope of the claims; furthermore, all the details are replaceable by technically equivalent elements.

    [0057] The materials used, as well as the dimensions, may in practice be of any type according to requirements and the state of the art.


    Claims

    1. A method for making an ice making machine comprising a coolant circuit comprising a coolant fluid based on a hydrocarbon, at least one evaporator on the surface of which the ice forms, at least one expansion valve, at least one compressor, and at least one condenser (1) comprising a fin pack (3) and one or more rows of tubes (4) with a circular section fixed in through holes (5) of said fins (3), said tubes (4) have micro-grooves (9) on their inner surface such that the inner surface of said tubes (4) is greater than the outer surface, said tubes (4) have a minimum inner thickness (d) comprised between 0.1 and 0.3 mm at the bottom of said micro-grooves (9), a maximum inner thickness (D) comprised between 0.15 and 0.6 mm at the top of said micro-grooves (9), and an outer diameter (Φ) comprised between 4 and 12 mm, said fins (3) and said tubes (4) are made of a different thermally conductive material, said tubes (4) have radially expanded section against said holes (5), the wall of said holes (5) have a plastic deformation (5') with which said holes (5) tighten firmly on said tubes (4), said at least one condenser (1) comprising a box-shaped support frame (2) having two flat side faces (2a, 2a) vertical and opposite, said support frame (2) housing said fin pack (3) and said tubes (4) arranged parallel to each other and with the longitudinal axis (L) horizontal and perpendicular with said two flat side faces (2a, 2a) in turn having support through holes of said tubes (4) from which the ends of said tubes (4) exit, said tubes (4) being arranged in groups, in each of which said tubes (4) are connected in series, at the outer side of said flat side faces (2a, 2a) of said frame (2), by means of 180° connectors (10, 10'), so as to form coils which may be supplied in parallel with the coolant fluid, the total inner volume of said tubes (4) being such as to house a quantity of coolant fluid not exceeding 150 grams, wherein said micro-grooves (9) extend along spiral lines of crushed thickness of said tubes without removal of material which wind around the longitudinal axis (L) of said tubes (4), wherein the method comprises the making of said micro-grooves (9) in said tubes of said at least one condenser of said ice-making machine by using an apparatus that comprises a tool (11) and a blocking device (14) for tightening connectors (10, 10') connecting the tubes, said tool (11) having a stem (12) which ends with a tapered work head (13), said tool (11) further having an axially translatable coaxial gripper (15) external to the stem (12) and provided with grip sectors (15a), wherein after fitting the fins (3) onto the tubes (4), the tubes (4) are blocked in position by means of the blocking device (14) which tightens the connectors (10, 10'), wherein initially the work head (13) of the tool (11) is pointed against an end of a tube (4) and the gripper (15) translates axially until it surmounts the end of the tube (4), and subsequently the gripper (15) tightens on the tube (4) causing its sectors (15a) to retract radially, and wherein with the gripper (15) tightened on the tube (4), the stem (12) translates axially in the direction of introduction into the tube (4) and the stem (12) rotates in a synchronised way on its own axis.
     
    2. A method for making an ice making machine according to claim 1, characterised in that said micro-grooves (9) have a spacing step not exceeding 1 mm.
     
    3. A method for making an ice making machine according to any one of the previous claims, characterised in that said hydrocarbon is propane.
     
    4. A method for making an ice making machine according to any one of the previous claims, characterised in that said tubes (4) are made of copper and said fins (3) are made of aluminium.
     


    Ansprüche

    1. Verfahren zur Herstellung einer Eismaschine, umfassend einen Kühlkreis, umfassend eine Kühlflüssigkeit, basierend auf Kohlenwasserstoff, mindestens einen Verdampfer, auf dessen Oberfläche sich das Eis bildet, mindestens ein Expansionsventil, mindestens einen Verdichter und mindestens einen Verflüssiger (1), umfassend ein Rippenpaket (3) und eine oder mehrere Reihen an Rohren (4) mit kreisförmigem Querschnitt, die in Durchführungslöchern (5) der Rippen (3) fixiert sind, wobei die Rohre (4) Mikrorillen (9) auf ihrer innenseitigen Oberfläche aufweisen, sodass die innenseitige Oberfläche der Rohre (4) größer als die außenseitige Oberfläche ist, wobei die Rohre (4) eine Mindestinnendicke (d) aufweisen, die zwischen 0,1 und 0,3 mm an der Unterseite der Mikrorillen (9) enthalten ist, eine maximale Innendicke (D), die zwischen 0,15 und 0,6 mm an der Oberseite der Mikrorillen (9) enthalten ist, und einen Außendurchmesser (φ), enthalten zwischen 4 und 12 mm, wobei die Rippen (3) und die Rohre (4) aus einem unterschiedlichen thermisch leitfähigen Material gefertigt sind, wobei die Rohre (4) einen radial erweiterten Querschnitt gegen die Löcher (5) aufweisen, die Wand der Löcher (5) eine plastische Verformung (5') aufweist, mit der die Löcher (5) fest an den Rohren (4) festgezogen sind, wobei der mindestens eine Verflüssiger (1) einen kastenförmigen Halterungsrahmen (2) umfasst, aufweisend zwei flache Seitenflächen (2a, 2a), die vertikal und gegenständig sind, wobei der Halterungsrahmen (2) das Rippenpaket (3) aufnimmt und die Rohre (4) parallel zueinander und zur Längsachse (L) horizontal und senkrecht mit den zwei flachen Seitenflächen (2a, 2a) angeordnet sind und wiederum Halterungsdurchführungslöcher der Rohre (4) aufweisen, von denen die Enden der Rohre (4) austreten, wobei die Rohre (4) in Gruppen angeordnet sind, und die Rohre (4) in einer jeden davon in Reihe an der äußeren Seite der flachen Seitenflächen (2a, 2a) des Rahmens (2) mittels 180°-Verbindungsstücken (10, 10') angeordnet sind, sodass Schlangen geformt werden, die parallel mit der Kühlflüssigkeit versorgt werden können, wobei das Gesamtinnenvolumen der Rohre (4) so beschaffen ist, dass eine Menge von Kühlflüssigkeit aufgenommen werden kann, die 150 g nicht überschreitet, wobei sich die Mikrorillen (9) entlang Spirallinien einer zerkleinerten Dicke der Rohre erstrecken, ohne Entfernung von Material, die sich rund um die Längsachse (L) der Rohre (4) winden, wobei das Verfahren die Ausbildung der Mikrorillen (9) in den Rohren des mindestens einen Verflüssigers der Eismaschine umfasst, durch die Nutzung eines Geräts, das ein Werkzeug (11) und eine Festspannvorrichtung (14) zum Festziehen der Verbindungsstücke (10, 10'), die die Rohre verbinden, umfasst, wobei das Werkzeug (11) einen Schaft (12) aufweist, der mit einem spitz zulaufenden Bearbeitungskopf (13) endet, wobei das Werkzeug (11) zudem einen axial verschiebbaren koaxialen Greifer (15) außerhalb des Schafts (12) umfasst, versehen mit Greifsektoren (15a), wobei die Rohre (4) nach dem Befestigen der Rippen (3) auf den Rohren (4) mittels der Festspannvorrichtung (14), die die Verbindungsstücke (10, 10') festzieht, festgespannt werden, wobei der Bearbeitungskopf (13) des Werkzeugs (11) anfänglich gegen ein Ende eines Rohrs (4) gerichtet ist und der Greifer (15) axial verschoben wird, bis er das Ende des Rohrs (4) überlagert, wobei der Greifer (15) entsprechend am Rohr (4) festgespannt wird und bewirkt, dass dessen Sektoren (15a) radial zurückgezogen werden, und wobei der Schaft (12) bei auf dem Rohr (4) festgespanntem Greifer (15) axial in die Einführungsrichtung in das Rohr (4) verschoben wird und sich der Schaft (12) synchron auf seiner eigenen Achse dreht.
     
    2. Verfahren zur Herstellung einer Eismaschine nach Anspruch 1, dadurch gekennzeichnet, dass die Mikrorillen (9) einen Beabstandungsschritt aufweisen, der 1 mm nicht überschreitet.
     
    3. Verfahren zur Herstellung einer Eismaschine nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass der Kohlenwasserstoff Propan ist.
     
    4. Verfahren zur Herstellung einer Eismaschine nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Rohre (4) aus Kupfer bestehen und die Rippen (3) aus Aluminium bestehen.
     


    Revendications

    1. Méthode pour construire une machine de fabrication de glaçons comprenant un circuit de refroidissement comprenant un fluide de refroidissement à base d'un hydrocarbure, au moins un évaporateur sur la surface duquel se forme la glace, au moins un détendeur, au moins un compresseur, et au moins un condensateur (1) comprenant un bloc d'ailettes (3) et une ou plusieurs rangées de tubes (4), à section circulaire, fixés dans des trous débouchants (5) desdites ailettes (3), lesdits tubes (4) comportent des micro-rainures (9) sur leur surface interne de sorte que la surface interne desdits tubes (4) soit supérieure à la surface externe, lesdits tubes (4) ont une épaisseur intérieure minimum (d) comprise entre 0,1 et 0,3 mm au fond desdites micro-rainures (9), une épaisseur intérieure maximum (D) comprise entre 0,15 et 0,6 mm au somment desdites micro-rainures (9), et un diamètre extérieur (Φ) compris entre 4 et 12 mm, lesdites ailettes (3) et lesdits tubes (4) sont constitués d'un matériau à conduction thermique différent, lesdits tubes (4) comportent une section étendue radialement contre lesdits trous (5), la cloison desdits trous (5) comporte une déformation plastique (5') avec laquelle lesdits trous (5) se serrent fermement sur lesdits tubes (4), ledit au moins un condensateur (1) comprenant un châssis de support en forme de boîtier (2) comportant deux côtés latéraux plats (2a, 2a) verticaux et opposés, ledit châssis de support (2) logeant ledit bloc d'ailettes (3) et lesdits tubes (4) disposés parallèlement les uns aux autres et avec l'axe longitudinal (L) horizontal et perpendiculaire auxdits deux côtés latéraux plats (2a, 2a) ayant à leur tour des trous débouchants de support desdits tubes (4) desquels sortent les extrémités desdits tubes (4), lesdits tubes (4) étant disposés en groupes, dans lesquels lesdits tubes (4) sont reliés en série en correspondance du côté extérieur desdits côtés latéraux plats (2a, 2a) dudit châssis (2), au moyen de connecteurs à 180° (10, 10'), de sorte à former des serpentins étant alimentés parallèlement avec le fluide de refroidissement, le volume interne total desdits tubes (4) étant tel qu'il est en mesure de loger une quantité de fluide de refroidissement n'excédant pas 150 grammes, dans laquelle lesdites micro-rainures (9) se prolongent le long de lignes en spirale d'épaisseur écrasée desdits tubes sans le retrait du matériau s'enroulant autour de l'axe longitudinal (L) desdits tubes (4), dans laquelle la méthode comprend la fabrication desdites micro-rainures (9) dans lesdits tubes dudit au moins un condensateur de ladite machine de fabrication de glaçons en utilisant un appareil comprenant un outil (11) et un dispositif de blocage (14) pour serrer des connecteurs (10, 10') reliant les tubes, ledit outil (11) comportant une tige (12) se terminant avec une tête de travail conique (13), ledit outil (11) comportant de plus un préhenseur coaxial (15) pouvant translater axialement extérieur à la tige (12) et pourvu de secteurs de préhension (15a), dans laquelle après montage des ailettes (3) sur les tubes (4), les tubes (4) sont bloqués en position au moyen d'un dispositif de blocage (14) qui serre les connecteurs (10, 10'), dans laquelle, initialement, la tête de travail (13) de l'outil (11) est pointée contre une extrémité d'un tube (4) et le préhenseur (15) translate axialement jusqu'à ce qu'il surmonte l'extrémité du tube (4), et subséquemment le préhenseur (15) se serre sur le tube (4) en provoquant la rétraction de ses secteurs (15a) radialement, et dans laquelle avec le préhenseur (15) serré sur le tube (4), la tige (12) translate axialement dans la direction d'introduction dans le tube (4) et la tige (12) tourne de façon synchronisée sur son propre axe.
     
    2. Méthode pour construire une machine de fabrication de glaçons selon la revendication 1, caractérisée en ce que lesdites micro-rainures (9) comportent un pas d'espacement n'excédant pas 1 mm.
     
    3. Méthode pour construire une machine de fabrication de glaçons selon l'une quelconque des revendications précédentes, caractérisée en ce que ledit hydrocarbure est du propane.
     
    4. Méthode pour construire une machine de fabrication de glaçons selon l'une quelconque des revendications précédentes, caractérisée en ce que lesdits tubes (4) sont en cuivre et lesdites ailettes (3) en aluminium.
     




    Drawing




















    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description