(19)
(11)EP 3 251 828 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
27.11.2019 Bulletin 2019/48

(21)Application number: 17168381.6

(22)Date of filing:  27.04.2017
(51)International Patent Classification (IPC): 
B32B 5/02(2006.01)
B32B 7/10(2006.01)
B32B 15/14(2006.01)
B32B 27/12(2006.01)
B32B 27/34(2006.01)
F16L 11/08(2006.01)
B32B 7/08(2019.01)
B32B 15/085(2006.01)
B32B 15/18(2006.01)
B32B 27/32(2006.01)
B32B 1/08(2006.01)

(54)

FLEXIBLE HOSE

FLEXIBLER SCHLAUCH

TUYAU FLEXIBLE


(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: 01.06.2016 GB 201609590

(43)Date of publication of application:
06.12.2017 Bulletin 2017/49

(73)Proprietor: Ultra Electronics Limited
Greenford, Middlesex UB6 8UA (GB)

(72)Inventors:
  • BECK, Robert
    Greenford, Middlesex UB6 8UA (GB)
  • COOPER, Ian
    Greenford, Middlesex UB6 8UA (GB)
  • HARDING, Simon
    Greenford, Middlesex UB6 8UA (GB)

(74)Representative: Wardle, Callum Tarn et al
Withers & Rogers LLP 4 More London Riverside
London SE1 2AU
London SE1 2AU (GB)


(56)References cited: : 
WO-A1-2015/013618
GB-A- 2 502 772
US-A1- 2007 221 281
CN-U- 204 986 084
US-A- 4 950 436
US-A1- 2015 247 032
  
      
    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



    [0001] The present application relates to a flexible hose.

    Background to the Invention



    [0002] Many applications in the aerospace industry require fluids such as compressed air, brake fluid, coolant and the like to be transported around an aircraft, vehicle or other structure, and a wide variety of hoses are available for these purposes. Known hoses function adequately in normal operating conditions, but can fail or deteriorate when used in extreme conditions such as at high altitude or in extremes of temperature. Failure or deterioration of these hoses can lead, at best, to reduced performance, and at worst to catastrophic failure of critical systems.

    [0003] One area where high performance hoses are required to operate in extreme conditions is in weapons and countermeasures systems for military aircraft. These systems require extremely high pressure (around 5000 psi) dry air to be delivered reliably at extreme altitudes and temperatures (e.g. temperatures in the range -70°C to +80°C), while remaining flexible in dynamic applications. These hoses are subject to fatigue caused by a combination of forces applied by the internal pressure and external inertial loads and flextural loads. As will be appreciated, in such systems, any deterioration or failure of the hose delivering the dry air could have serious adverse consequences.

    [0004] Accordingly, a need exists for a high performance hose that is able to carry fluids at extremely high pressure and to operate reliably in hostile environments and at extremes of temperature.

    [0005] US2007221281 discloses a composite hose with a corrugated metal tube having a hose body having a corrugated metal tube and an outer layer. The corrugated metal tube includes a non-corrugated straight-walled portion on an end portion thereof, and a rigid insert pipe is inserted in the straight-walled portion. A socket fitting is fitted on the hose body.

    Summary of Invention



    [0006] According to a first aspect of the present invention there is provided a flexible hose comprising: a flexible conduit for carrying a pressurised fluid; a flexible inner support for supporting the conduit; and a compression layer surrounding the flexible conduit.
    The combination of the flexible conduit, flexible inner support and compression layer gives rise to a water and air impermeable, strong, durable and robust hose that nevertheless remains flexible, and flexes in a predictable and repeatable manner, and can be used for demanding applications in hostile environments and extremes of temperature. The flexible inner support is provided, on an outer surface thereof, with a helical coil or thread formation, and the flexible conduit may be provided, on an inner surface thereof, with a complementary helical coil or thread formation which, when the flexible hose is assembled, engages with the helical coil or thread formation of the inner support to maintain the conduit in position relative to the inner support.

    [0007] The flexible hose may further comprise an outer sleeve.

    [0008] The flexible inner support may comprise a flexible and chemically stable polymer material.

    [0009] The flexible and chemically stable polymer material may comprise polytetrafluoroethylene (PTFE), for example.

    [0010] The conduit may comprise stainless steel tubing.

    [0011] The compression layer may comprises a sleeve of braided material.

    [0012] The braided material may comprise Nomex®, for example.

    [0013] The outer sleeve may be of a polymer material.

    [0014] The outer sleeve may be of a heat-shrink material.

    [0015] For example, the outer sleeve may be of Raychem DR-25™ heat-shrinkable tubing.

    Brief Description of the Drawings



    [0016] Embodiments of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, of which:

    Figure 1 is a schematic cutaway view from one side of a section of flexible hose; and

    Figure 2 is a schematic cutaway cross-sectional view of the section of flexible hose shown in Figure 1.


    Description of the Embodiments



    [0017] Referring first to Figure 1, a section of hose is shown generally at 10. The hose 10 comprises a flexible, hollow, inner support 20 of a water and air impermeable material. In the illustrated example an outer surface of the inner support 20 is formed with a continuous helical coil or thread formation 22, though it is to be appreciated that the inner support 20 may be formed without this helical coil or thread formation. The inner support is made of a chemically stable polymer material, such as polytetrafluoroethylene (PTFE), or a similar chemically stable polymer.

    [0018] The inner support 20 is received within and acts as a support for a conduit 30 which carries high-pressure air through the hose 10. The conduit 30 is made from a metal such as stainless steel, and is formed from a flexible tube which, in the illustrated example, has an inner surface that is formed with a continuous helical coil or thread formation 32 that is complementary to the helical coil or thread formation 22 of the inner support 20. It is to be appreciated, however, that the conduit 30 may be formed without this helical coil or thread formation. The conduit 30 may be formed, for example, of 1/16" helically wound stainless steel tubing. Stainless steel is preferred for the conduit 30, as it is able to function in the required temperature range (-70°C to +80°C) and has the required air impermeability properties.

    [0019] When the hose 10 is assembled the coil or thread formation 32 of the inner surface of the conduit 30 is threaded onto or interleaved with the coil or thread formation 22 of the outer surface of the inner support 20. This engagement of the coil or thread formation 32 of the conduit 30 with the coil or thread formation 22 of the inner support 20 helps to maintain the conduit 30 in position with respect to the inner support 20. However, where the coil or thread formations 22, 32 are not provided there is minimal risk of displacement of the conduit 30 with respect to the inner support 20, as other components of the hose 10 provide a compressive force which helps to maintain the conduit 30 in position, as will be explained in more detail below.

    [0020] The inner support 20 provides a flexible support for the conduit 30. The inner support 20 helps to prevent the conduit 30 from shifting during flexing of the hose and, and from collapsing at high bend radii. This arrangement of the conduit 30 being supported by the inner support 20 allows the conduit 30 to flex in a predictable and repeatable way, and helps to distribute stress in the hose 10, thereby reducing fatigue and increasing durability, thus leading to improved dynamic fatigue performance.

    [0021] Surrounding the conduit 30 is a compression layer 40, which applies a compressive force to the conduit 30, which helps to maintain the conduit 30 in position relative to the inner support 20. This is particularly useful where the inner support 20 and the conduit 30 are provided without the complementary coil or thread formations 22, 32. The compression layer 40 also affords a degree of protection for the conduit 30 and the inner support 20 against mechanical abrasion and extremes of heat and cold. The compression layer 40 may be formed as a braided sleeve. A particularly suitable material for the braided sleeve is Nomex®, manufactured by DuPont, as this material has been found to be lightweight, flexible, durable and water repellent. The braided structure of the compression layer 40 facilitates manufacture of the hose 10, as the sleeve can expand to fit over the conduit 30. Moreover, the braided structure does not impede bending and flexing of the inner support 20 and the conduit 30.

    [0022] An outer sleeve 50 of a polymer material may be provided, surrounding the compression layer 40. The outer sleeve 50 provides a further layer of abrasion and fluid resistance without impeding the flexibility of the hose 10. The sleeve 50 may be provided, for example, as a tube of heat-shrinkable material into which the assembly of the inner support 20, conduit 30 and compression layer 40 can be placed, with the sleeve then being heated to shrink to form the outer sleeve 50. A particularly suitable material for the outer sleeve is Raychem DR-25™.

    [0023] In some embodiments the compression layer 40 and the outer sleeve 50 may be provided as a single layer.

    [0024] The hose 10 may be provided at its ends with pneumatic hose connectors of any suitable type, to facilitate connection of the hose 10 to other components in a high pressure compressed air system.

    [0025] The combination of the inner support 20, conduit 30, compression layer 40 and outer sleeve 50 gives rise to a high-performance, water and air impermeable, strong, durable and robust hose 10 with excellent dynamic fatigue performance that nevertheless remains flexible (and flexes in a repeatable and predictable manner), and can be used for demanding applications in hostile environments and extremes of temperature. For example, the hose 10 is particular suited to aerospace applications where extremely high pressure dry air (at around 5000 psi) is required.


    Claims

    1. A flexible hose (10) comprising:

    a flexible conduit (30) for carrying a pressurised fluid;

    a flexible inner support (20) for supporting the conduit; and

    a compression layer (40) surrounding the flexible conduit; and

    wherein the flexible inner support is provided, on an outer surface thereof, with a helical coil or thread formation (22), and wherein the flexible conduit is provided, on an inner surface thereof, with a complementary helical coil or thread formation (32) which, when the flexible hose is assembled, engages with the helical coil or thread formation of the inner support to maintain the conduit in position relative to the inner support.


     
    2. A flexible hose according to claim 1 further comprising an outer sleeve (50).
     
    3. A flexible hose according to any one of the preceding claims wherein the flexible inner support comprises a flexible and chemically stable polymer material.
     
    4. A flexible hose according to claim 3 wherein the flexible polymer material comprises polytetrafluoroethylene (PTFE).
     
    5. A flexible hose according to any one of the preceding claims wherein the conduit comprises stainless steel tubing.
     
    6. A flexible hose according to any one of the preceding claims wherein the compression layer comprises a sleeve of braided material.
     
    7. A flexible hose according to claim 6 wherein the braided material comprises Nomex®.
     
    8. A flexible hose according to any one of the claims 2 to 7 wherein the outer sleeve is of a polymer material.
     
    9. A flexible hose according to claim 8 wherein the outer sleeve is of a heat-shrink material.
     


    Ansprüche

    1. Flexibler Schlauch (10), umfassend:

    eine flexible Leitung (30) zum Führen eines Druckfluids;

    eine flexible innere Stütze (20) zum Stützen der Leitung; und

    eine die flexible Leitung umschließende Kompressionsschicht (40);

    wobei die flexible innere Stütze an ihrer Außenfläche mit einer helikalen Wendel oder Gewindeausbildung (22) versehen ist und wobei die flexible Leitung an ihrer Innenfläche mit einer komplementären helikalen Wendel oder Gewindeausbildung (32) versehen ist, die bei der Montage des flexiblen Schlauchs mit der helikalen Wendel oder Gewindeausbildung der inneren Stütze zusammenwirkt, um die Leitung relativ zur inneren Stütze in Position zu halten.


     
    2. Flexibler Schlauch nach Anspruch 1, ferner umfassend eine Außenhülle (50).
     
    3. Flexibler Schlauch nach einem der vorangehenden Ansprüche, wobei die flexible innere Stütze ein flexibles und chemisch stabiles Polymermaterial umfasst.
     
    4. Flexibler Schlauch nach Anspruch 3, wobei das flexible Polymermaterial Polytetrafluorethylen (PTFE) umfasst.
     
    5. Flexibler Schlauch nach einem der vorangehenden Ansprüche, wobei die Leitung ein rostfreies Stahlrohr umfasst.
     
    6. Flexibler Schlauch nach einem der vorangehenden Ansprüche, wobei die Kompressionsschicht eine Hülse aus geflochtenem Material umfasst.
     
    7. Flexibler Schlauch nach Anspruch 6, wobei das geflochtene Material Nomex® umfasst.
     
    8. Flexibler Schlauch nach einem der Ansprüche 2 bis 7, wobei die Außenhülse aus einem Polymermaterial besteht.
     
    9. Flexibler Schlauch nach Anspruch 8, wobei die Außenhülse aus wärmeschrumpfbarem Material besteht.
     


    Revendications

    1. Tuyau flexible (10) comprenant :

    une conduite flexible (30) destinée à transporter un fluide sous pression,

    un support interne flexible (20) destiné à supporter la conduite, et

    une couche de compression (40) entourant la conduite flexible,

    le support interne flexible comportant, sur sa surface externe, une conformation en serpentin hélicoïdal ou en filetage (22), et la conduite flexible comportant, sur sa surface interne, une conformation en serpentin hélicoïdal ou en filetage (32) complémentaire, qui, lorsque le tuyau flexible est assemblé vient en prise avec la conformation en serpentin hélicoïdal ou en filetage du support interne pour maintenir la conduite en position par rapport au support interne.


     
    2. Tuyau flexible conforme à la revendication 1,
    comprenant en outre un manchon externe (50).
     
    3. Tuyau flexible conforme à l'une quelconque des revendications précédentes,
    dans lequel le support interne flexible renferme un matériau polymère flexible et chimique stable.
     
    4. Tuyau flexible conforme à la revendication 3,
    dans lequel le matériau polymère flexible renferme du poly-tétra-fluoréthylène (PTFE).
     
    5. Tuyau flexible conforme à l'une quelconque des revendications précédentes,
    dans lequel la conduite comporte un tubage en acier inoxydable.
     
    6. Tuyau flexible conforme à l'une quelconque des revendications précédentes,
    dans lequel la couche de compression comporte un manchon en matériau tressé.
     
    7. Tuyau flexible conforme à la revendication 6,
    dans lequel le matériau tressé renferme du Nomex®.
     
    8. Tuyau flexible conforme à l'une quelconque des revendications 2 à 7, dans lequel le manchon externe est réalisé en un matériau polymère.
     
    9. Tuyau flexible conforme à la revendication 8,
    dans lequel le manchon externe est réalisé en un matériau thermorétractable.
     




    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