(19)
(11)EP 3 299 667 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
17.06.2020 Bulletin 2020/25

(21)Application number: 17192695.9

(22)Date of filing:  22.09.2017
(51)International Patent Classification (IPC): 
F16H 57/02(2012.01)
B64C 27/12(2006.01)
F16H 57/04(2010.01)

(54)

FAN WITH LABYRINTH SEAL FOR PREVENTION OF WATER DAMAGE TO A GEARBOX

LÜFTER MIT LABYRINTHDICHTUNG ZUR PRÄVENTION VON WASSERSCHÄDEN AN EINEM GETRIEBE

VENTILATEUR AVEC JOINT À LABYRINTHE POUR LA PRÉVENTION DE DOMMAGES LIÉS À L'EAU SUR UNE BOÎTE DE VITESSES


(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: 23.09.2016 US 201662399097 P
17.11.2016 US 201662423371 P
14.09.2017 US 201715704355

(43)Date of publication of application:
28.03.2018 Bulletin 2018/13

(73)Proprietor: Bell Helicopter Textron Inc.
Fort Worth, TX 76101 (US)

(72)Inventor:
  • POSTER, Scott David
    Arlington, TX 76016 (US)

(74)Representative: Barker Brettell LLP 
100 Hagley Road Edgbaston
Birmingham B16 8QQ
Birmingham B16 8QQ (GB)


(56)References cited: : 
EP-A1- 2 505 878
JP-A- H0 835 499
US-A1- 2016 258 526
WO-A1-2016/018498
US-A1- 2013 089 409
US-B1- 7 025 356
  
      
    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

    TECHNICAL FIELD OF THE INVENTION



    [0001] The present invention relates in general to the field of water penetration, and more particularly, to an apparatus and method for preventing water damage to a gearbox.

    BACKGROUND OF THE INVENTION



    [0002] Without limiting the scope of the invention, its background is described in connection with lubrication systems.

    [0003] One such invention is taught in U.S. Patent No. 9,458,923, issued to Poster, et al., entitled "Gearbox with passive lubrication system." These inventors teach a lubrication system that includes a reserve housing configured to retain a lubrication fluid. A supply line in fluid communication with the reserve housing is configured to provide pressurized lubrication fluid to the reserve housing. An overflow tube has an overflow port, the overflow tube being configured to prevent the volume of the lubrication fluid from exceeding a certain amount. A metering jet is configured to allow the lubrication fluid to flow from the reserve housing onto a component, such as a bearing, in the gearbox at a predetermined rate. The metering jet provides flow of the lubrication fluid onto the bearing even when the supply line no longer provides pressurized lubrication fluid to the reserve housing.

    [0004] WO2016/018498A1 discloses a gearbox oil cooling assembly for a gearbox driving a drive shaft having a drive shaft coupling. The assembly includes a heat exchanger to receive and cool an oil from the gearbox and having an inlet. Also included is an impeller axially disposed between the heat exchanger and the drive shaft coupling, wherein the impeller is operatively coupled to, and rotated by, the drive shaft operatively coupled to the drive shaft coupling. Further included is an exhaust duct operatively coupled to the heat exchanger and disposed radially outwardly around the impeller and defining an airflow pathway through which air passes through the inlet, the impeller and through the exhaust duct according to the rotation of the impeller to cool the oil in the heat exchanger.

    SUMMARY OF THE INVENTION



    [0005] The present invention includes a system for preventing or reducing water penetration of a gearbox, as defined in claim 1. In one embodiment, the gearbox is connected to an engine in a car, truck, locomotive, aircraft, or rotorcraft. In another embodiment, the gearbox is a main rotor gearbox, an intermediate gearbox, or a tail rotor gearbox of a rotorcraft. In another embodiment, the system further includes one or more cooling fins, wherein the one or more cooling fins are metal, composite, ceramic, polymer, or combinations thereof. In another embodiment, the gearbox is a pressurized gearbox or a non-pressurized gearbox. In another embodiment, the gearbox is a pressurized gearbox using a pressurized lubricant. In another embodiment, the pressurized lubricant is a petroleum lubricant, a mineral oil, a plant oil, a synthetic lubricant, a high temperature lubricant, or combinations thereof. In another embodiment, the gearbox further includes at least one of: a filter, a pump, a bearing, or one or more valves for the pressurized lubricant. In another embodiment, the system further includes an active cooling system for the pressurized lubricant. In another embodiment, the gearbox is at least partially lubricated by the pressurized lubricant.

    [0006] In a non-claimed aspect, there is provided a system for preventing or reducing water penetration of a gearbox of an aircraft, the system including a gearbox; and a fan assembly including a fan and a hub, the fan assembly positioned proximate to the gearbox, wherein the hub is coupled to the fan and creates a labyrinth seal that prevents or reduces water penetration into the gearbox. In one embodiment, the gearbox is connected to an engine in a car, truck, locomotive, aircraft, or rotorcraft. In another embodiment, the gearbox is a main rotor gearbox, an intermediate gearbox, or a tail rotor gearbox of a rotorcraft. In another embodiment, the system further includes one or more cooling fins, wherein the one or more cooling fins are metal, composite, ceramic, polymer, or combinations thereof. In another embodiment, a length and a width of each the one or more cooling fins are modified to optimize an amount of heat convected by the cooling fins. In another embodiment, the gearbox is a pressurized gearbox using a pressurized lubricant. In another embodiment, the pressurized lubricant is a petroleum lubricant, a mineral oil, a plant oil, a synthetic lubricant, a high temperature lubricant, or combinations thereof. In another embodiment, the gearbox further includes at least one of: a filter, a pump, a bearing, or one or more valves for the pressurized lubricant. In another embodiment, the system further includes an active cooling system for the lubricant.

    [0007] The present invention includes a method preventing or reducing water penetration of a gearbox, as defined in claim 11.

    [0008] The present invention includes a kit for preventing or reducing water penetration of a gearbox, as defined in claim 12.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0009] For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures and in which:

    FIG. 1 shows a side view of a helicopter according to a preferred embodiment of the present application;

    FIG. 2 shows a partial cross-section, perspective view of helicopter aircraft according to an alternative embodiment of the present application;

    FIG. 3 is an isometric view of one exemplary and non-limiting example of a gearbox for a tail rotor of a rotorcraft that includes the present invention; and

    FIG. 4 shows a cross-sectional view of the fan in relation to the top of the gearbox.


    DETAILED DESCRIPTION OF THE INVENTION



    [0010] Illustrative embodiments of the system of the present application are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

    [0011] In the specification, reference may be made to the spatial relationships between various components and to the spatial orientation of various aspects of components as the devices are depicted in the attached drawings. However, as will be recognized by those skilled in the art after a complete reading of the present application, the devices, members, apparatuses, etc. described herein may be positioned in any desired orientation. Thus, the use of terms such as "above," "below," "upper," "lower," or other like terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the device described herein may be oriented in any desired direction.

    [0012] This invention is generally in the field of drive systems, and relates specifically to pressurized and non-pressurized gearboxes that are cooled through convection to the surrounding environment. Specifically, this invention relates to a labyrinth seal on an existing fan used on many gearboxes, including but not limited to pressurized gearboxes and non-pressurized gearboxes such as splash-lubricated gearboxes. The invention addresses a common failure point gearboxes.

    [0013] FIG. 1 shows an aircraft 100 in accordance with a preferred embodiment of the present application. In the exemplary embodiment, aircraft 100 is a helicopter having a fuselage 102 and a rotor system 104 carried thereon. A plurality of rotor blades 106 is operably associated with a rotor system 104 for creating flight. A tail boom 108 is depicted that further includes tail rotor 110.

    [0014] For example, FIG. 2 shows a partial cross-section isometric view of helicopter 100 that includes additional detail of the present invention. Helicopter 100 further includes a rotor mast 112, which is connected to the main transmission 114. The main transmission 114 is connected to one or more accessory gear boxes 116. The main transmission is connected to an engine 120, which is in an engine compartment 118. A tail rotor drive shaft 122 transmits mechanical rotation to the intermediate gear box 128, which is connected to the tail rotor gear box 124 via tail rotor drive shaft 126.

    [0015] FIG. 3 is an isometric view of one exemplary and non-limiting example of a gearbox 200 for a tail rotor of a rotorcraft that shows the fan and hub of the present invention. In this figure, a pressurized intermediate gearbox is depicted, however, the present invention can be used with a variety of other types of gearboxes, and to provide both cooling and a prevention or reduction of water penetration into the gearbox. While a pressurized gearbox 200 is depicted, the present invention can be used with any pressurized or non-pressurized gearbox. gearbox 200 as illustrated here includes pressurized gear mechanism 202, in this case is shown with a first and a second pressurized annuli 204a, 204b, shown with cooling fins 206a, 206b, respectively. The first and a second pressurized annuli 204a, 204b, radiate heat from a pressurized lubricating fluid or oil within the first and second pressurized annuli 204a, 204b via cooling fins 206a, 206b, to actively reduce the temperature of the pressurized lubricating fluid or oil in contact with the gearbox housing. A fan or impeller 208 is depicted that is above the pressurized gearbox 200 and that provides forced air cooling to the pressurized gearbox 200, which increases the cooling of the pressurized gearbox 200 and/or lubricating fluid within the same via cooling fins 206a, 206b. The fan or impeller 208 also includes a hub 210 (see FIG. 4) that is shaped to be a labyrinth seal to prevent or reduce water intrusion of the pressurized gearbox 200. The present invention can be used with any gearbox that may be subject to water penetration. Non-limiting examples of where a pressurized gearbox 200 can be used includes the main engine to transmission gearbox, any gears used as couplers, the main rotor gearbox, the intermediate gearbox, or the tail rotor gearbox.

    [0016] FIG. 4 shows a cross-sectional view of the fan or impeller 208 and hub 210 in relation to the top of the gearbox. The shaft 212 from the gearbox connects to the shaft 214 that transfers rotational power from the gearbox to another component of the aircraft, such as a tail rotor, main rotor or another transmission. The fan or impeller 208 is depicted with fan blades 222 in relation to the hub 210. Oil seal 216 is positioned against the outside of shaft 214 to keep lubricant in gearbox 200 and to prevent contaminants from entering gearbox 200, but oil seal 216 is generally not sufficient by itself to prevent water intrusion.

    [0017] While described in the form of a fan or impeller 208, the present invention can use any type of mechanical, electrical, electro-mechanical, pneumatic, hydraulic or other type of power to drive a fan or impeller having any shape to aid in cooling the gearbox and preventing water penetration. Non-limiting types of fans or impellers includes, e.g., axial, centrifugal, cross-flow, bellows, coanda effect, convective or electrostatic. In certain embodiments, the fan or impeller 208 is driven by gearbox 200, but in other embodiments, fan or impeller 208 may be driven by electric fans that are powered by shaded pole AC motors, or brushed or brushless DC motors.

    [0018] It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.

    [0019] All publications and patent applications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

    [0020] The use of the word "a" or "an" when used in conjunction with the term "comprising" in the claims and/or the specification may mean "one," but it is also consistent with the meaning of "one or more," "at least one," and "one or more than one." The use of the term "or" in the claims is used to mean "and/or" unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and "and/or." Throughout this application, the term "about" is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.

    [0021] As used in this specification and claim(s), the words "comprising" (and any form of comprising, such as "comprise" and "comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include") or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps. In embodiments of any of the compositions and methods provided herein, "comprising" may be replaced with "consisting essentially of' or "consisting of'. As used herein, the phrase "consisting essentially of' requires the specified integer(s) or steps as well as those that do not materially affect the character or function of the claimed invention. As used herein, the term "consisting" is used to indicate the presence of the recited integer (e.g., a feature, an element, a characteristic, a property, a method/process step, or a limitation) or group of integers (e.g., feature(s), element(s), characteristic(s), property(ies), method/process step(s), or limitation(s)) only.

    [0022] The term "or combinations thereof' as used herein refers to all permutations and combinations of the listed items preceding the term. For example, "A, B, C, or combinations thereof' is intended to include at least one of: A, B, C, AB, AC, BC, or ABC, and if order is important in a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this example, expressly included are combinations that contain repeats of one or more item or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan will understand that typically there is no limit on the number of items or terms in any combination, unless otherwise apparent from the context.

    [0023] As used herein, words of approximation such as, without limitation, "about," "substantial," or "substantially" refers to a condition that when so modified is understood to not necessarily be absolute or perfect but would be considered close enough to those of ordinary skill in the art to warrant designating the condition as being present. The extent to which the description may vary will depend on how great a change can be instituted and still have one of ordinary skill in the art recognize the modified feature as still having the required characteristics and capabilities of the unmodified feature. In general, but subject to the preceding discussion, a numerical value herein that is modified by a word of approximation such as "about" may vary from the stated value by at least ±1, 2, 3, 4, 5, 6, 7, 10, 12 or 15%.


    Claims

    1. A system for providing cooling and preventing or reducing water penetration of a gearbox (200), the system comprising:

    a fan or impeller (208) coupled to the gearbox (200);

    a hub (210) coupled to the fan (208); and

    characterized in that said hub is shaped to provide a labyrinth seal that prevents or reduces water penetration into the gearbox (200); and the system further comprises one or more cooling fins (206a, 206b).


     
    2. The system of claim 1, wherein the gearbox (200) is connected to an engine in a car, truck, locomotive, aircraft, or rotorcraft.
     
    3. The system of claim 1, wherein the gearbox (200) is a main rotor gearbox, an intermediate gearbox, or a tail rotor gearbox of a rotorcraft.
     
    4. The system of claim 1, wherein a length and a width of each the one or more cooling fins (206a, 206b) are modified to optimize an amount of heat convected by the cooling fins (206a, 206b).
     
    5. The system of any preceding claim, wherein the gearbox (200) is a pressurized gearbox or a non-pressurized gearbox.
     
    6. The system of claim 4 or of claim 5, wherein the gearbox (200) is a pressurized gearbox using a pressurized lubricant.
     
    7. The system of claim 6, wherein the pressurized lubricant is a petroleum lubricant, a mineral oil, a plant oil, a synthetic lubricant, a high temperature lubricant, or combinations thereof.
     
    8. The system of claim 6 or of claim 7, wherein the gearbox further (200) comprises at least one of: a filter, a pump, a bearing, or one or more valves for the pressurized lubricant.
     
    9. The system of any of claims 6 to 8, further comprising an active cooling system for the pressurized lubricant.
     
    10. The system of any of claims 6 to 9, wherein the gearbox (200) is at least partially lubricated by the pressurized lubricant.
     
    11. A method for providing cooling and preventing or reducing water penetration of a gearbox (200), the method comprising:

    disposing a fan assembly comprising a fan (208) and a hub (210) positioned proximate to the gearbox (200);

    and characterized in that said hub (210) creates a labyrinthine path that prevents or reduces water penetration into the gearbox (200); and the method further comprises disposing one or more cooling fins (206a, 206b) proximate to the gearbox (200).


     
    12. A kit for providing cooling and preventing or reducing water penetration of a gearbox (200), the kit comprising:

    a fan assembly comprising a fan (208) and a hub (210) positioned proximate to the gearbox (200);

    instructions for placing the fan assembly proximate to the gearbox (200) to prevent or reduce water penetration of the gearbox (200); and

    characterized in that said hub creates a labyrinthine path that prevents or reduces water penetration into the gearbox (200); and

    the kit further comprises one or more cooling fins (206a, 206b).


     


    Ansprüche

    1. System zum Vorsehen einer Kühlung und Verhindern oder Verringern des Eindringens von Wasser in ein Getriebe (200), wobei das System Folgendes umfasst:

    ein Leitrad oder einen Impeller (208), das/der mit dem Getriebe (200) gekoppelt ist;

    eine mit dem Leitrad (208) gekoppelte Nabe (210); und

    dadurch gekennzeichnet, dass die Nabe geformt ist, um eine Labyrinthdichtung vorzusehen, die das Eindringen von Wasser in das Getriebe (200) verhindert oder verringert; und dass das System ferner eine oder mehrere Kühlungslamellen (206a, 206b) umfasst.


     
    2. System nach Anspruch 1, wobei das Getriebe (200) mit einem Motor in einem PKW, einem LKW, einer Lokomotive, einem Flugzeug oder einem Drehflügler verbunden ist.
     
    3. System nach Anspruch 1, wobei das Getriebe (200) ein Hauptrotorgetriebe, ein Zwischengetriebe oder ein Heckrotorgetriebe eines Drehflüglers ist.
     
    4. System nach Anspruch 1, wobei die Länge und Breite jeder der einen oder mehreren Kühlungslamellen (206a, 206b) modifiziert sind, um die von den Kühlungslamellen (206a, 206b) geleitete Wärmemenge zu optimieren.
     
    5. System nach einem der vorstehenden Ansprüche, wobei das Getriebe (200) ein druckbeaufschlagtes Getriebe oder ein nicht druckbeaufschlagtes Getriebe ist.
     
    6. System nach Anspruch 4 oder Anspruch 5, wobei das Getriebe (200) ein druckbeaufschlagtes Getriebe ist, das ein druckbeaufschlagtes Schmiermittel verwendet.
     
    7. System nach Anspruch 6, wobei das druckbeaufschlagte Schmiermittel ein Petroleumschmiermittel, ein Mineralöl, ein Pflanzenöl, ein synthetisches Schmiermittel, ein Hochtemperaturschmiermittel oder Kombinationen davon ist.
     
    8. System nach Anspruch 6 oder Anspruch 7, wobei das Getriebe (200) ferner mindestens eines der folgenden Elemente umfasst: einen Filter, eine Pumpe, ein Lager oder ein oder mehrere Ventile für das druckbeaufschlagte Schmiermittel.
     
    9. System nach einem der Ansprüche 6 bis 8, ferner ein aktives Kühlungssystem für das druckbeaufschlagte Schmiermittel umfassend.
     
    10. System nach einem der Ansprüche 6 bis 9, wobei das Getriebe (200) zumindest teilweise mit dem druckbeaufschlagten Schmiermittel geschmiert ist.
     
    11. Verfahren zum Vorsehen einer Kühlung und Verhindern oder Verringern des Eindringens von Wasser in ein Getriebe (200), wobei das Verfahren Folgendes umfasst:

    Anordnen einer Leitradanordnung, ein Leitrad (208) und eine Nabe (210) umfassend, die in der Nähe des Getriebes (200) positioniert ist; und

    dadurch gekennzeichnet, dass die Nabe (210) einen Labyrinthweg erzeugt, der das Eindringen von Wasser in das Getriebe (200) verhindert oder verringert; und dass das Verfahren ferner das Anordnen einer oder mehrerer Kühlungslamellen (206a, 206b) in der Nähe des Getriebes (200) umfasst.


     
    12. Satz zum Vorsehen einer Kühlung und Verhindern oder Verringern des Eindringens von Wasser in ein Getriebe (200), wobei der Satz Folgendes umfasst:

    eine Leitradanordnung, ein Leitrad (208) und eine Nabe (210) umfassend, die in der Nähe des Getriebes (200) positioniert ist;

    eine Anleitung zum Platzieren der Leitradanordnung in der Nähe des Getriebes (200), um das Eindringen von Wasser in das Getriebe (200) zu verhindern oder zu verringern; und

    dadurch gekennzeichnet, dass die Nabe einen Labyrinthweg erzeugt, der das Eindringen von Wasser in das Getriebe (200) verhindert oder verringert; und

    dass der Satz ferner eine oder mehrere Kühlungslamellen (206a, 206b) umfasst.


     


    Revendications

    1. Système permettant d'assurer le refroidissement et d'empêcher ou de réduire la pénétration d'eau dans une boîte de vitesses (200), le système comprenant :

    un ventilateur ou une roue (208) accouplé à la boîte de vitesses (200) ;

    un moyeu (210) accouplé au ventilateur (208) ; et

    caractérisé en ce que ledit moyeu est formé de sorte à fournir un joint à labyrinthe qui empêche ou réduit la pénétration d'eau dans la boîte de vitesses (200) ; et le système comprend en outre au moins une ailette de refroidissement (206a, 206b).


     
    2. Système selon la revendication 1, la boîte de vitesses (200) étant reliée à un moteur dans une voiture, un camion, une locomotive, un aéronef ou un giravion.
     
    3. Système selon la revendication 1, la boîte de vitesses (200) étant une boîte de vitesses de rotor principal, une boîte de vitesses intermédiaire ou une boîte de vitesses de rotor de queue d'un giravion.
     
    4. Système selon la revendication 1, une longueur et une largeur de chacune de l'au moins une ailette de refroidissement (206a, 206b) étant modifiées pour optimiser une quantité de chaleur envoyée par les ailettes de refroidissement (206a, 206b).
     
    5. Système selon l'une quelconque des revendications précédentes, la boîte de vitesses (200) étant une boîte de vitesses sous pression ou une boîte de vitesses pas sous pression.
     
    6. Système selon la revendication 4 ou 5, la boîte de vitesses (200) étant une boîte de vitesses sous pression utilisant un lubrifiant sous pression.
     
    7. Système selon la revendication 6, le lubrifiant sous pression étant un lubrifiant à base de pétrole, une huile minérale, une huile végétale, un lubrifiant synthétique, un lubrifiant à haute température, ou des combinaisons de ceux-ci.
     
    8. Système selon la revendication 6 ou 7, la boîte de vitesses (200) comprenant en outre au moins un des éléments suivants : un filtre, une pompe, un palier ou au moins une soupape pour le lubrifiant sous pression.
     
    9. Système selon l'une quelconque des revendications 6 à 8, comprenant en outre un système de refroidissement actif pour le lubrifiant sous pression.
     
    10. Système selon l'une quelconque des revendications 6 à 9, la boîte de vitesses (200) étant au moins partiellement lubrifiée par le lubrifiant sous pression.
     
    11. Procédé pour assurer le refroidissement et empêcher ou réduire la pénétration d'eau dans une boîte de vitesses (200), le procédé comprenant les étapes consistant à :

    disposer d'un ensemble ventilateur comprenant un ventilateur (208) et un moyeu (210) positionné à proximité de la boîte de vitesses (200) ;

    et caractérisé en ce que ledit moyeu (210) crée un chemin labyrinthique qui empêche ou réduit la pénétration d'eau dans la boîte de vitesses (200) ; et le procédé comprend en outre l'étape consistant à disposer au moins une ailette de refroidissement (206a, 206b) à proximité de la boîte de vitesses (200).


     
    12. Kit pour assurer le refroidissement et empêcher ou réduire la pénétration d'eau dans une boîte de vitesses (200), le kit comprenant :

    un ensemble ventilateur comprenant un ventilateur (208) et un moyeu (210) positionné à proximité de la boîte de vitesses (200) ;

    des instructions pour placer l'ensemble ventilateur à proximité de la boîte de vitesses (200) afin d'empêcher ou de réduire la pénétration d'eau dans la boîte de vitesses (200) ; et

    caractérisé en ce que ledit moyeu crée un chemin labyrinthique qui empêche ou réduit la pénétration d'eau dans la boîte de vitesses (200) ; et

    le kit comprenant en outre au moins une ailette de refroidissement (206a, 206b).


     




    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