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Publication numberUS2758194 A
Publication typeGrant
Publication dateAug 7, 1956
Filing dateApr 27, 1954
Priority dateMay 5, 1953
Publication numberUS 2758194 A, US 2758194A, US-A-2758194, US2758194 A, US2758194A
InventorsAndrew G Heron
Original AssigneeAndrew G Heron
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Flexible hoses
US 2758194 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

g- 7, 1956 A. G. HERON 2,758,194

FLEXIBLE HOSES Filed April 2?,1954

2 Shets-Sheet 1 Aug. 7, 1 956 FLEXIBLE HOSES Filed April 27, 1954 2 Sheets-Sheet 2 5 Fig. 5.

I In em;k

A. G. HERON 2,758,194

United States Patent FLEXIBLE HOSES Andrew G. Heron, Newcastle-upon-Tyne, England Application April 27, 1954, Serial No. 425,998 Claims priority, application Great Britain May 5, 1953 2 Claims. (Cl. 219-46) This invention relates to electrically heated flexible hoses of the kind comprising conductor means associated with the hose, and adapted to be connected to a low voltage supply source.

If such a heating hose could be made which would be reliable under all conditions of use, it would fulfill a great need on account of the many uses it would have, one of which, for example, is the conveying of viscous paint for coating a ships hull. Hence a number of proposals have been made, but none, apparently, with much success.

In some proposals, the hose comprised heating resistance wires in the form of helically wound heating elements, or an electric heating resistance cable wound round the hose, arranged in passages formed in the wall of the hose, or incorporated in the hose. In other proposals, the hose was a flexible metal tube of helical form or of articulated sections. The conductors were variously connected to the usual supply source or to the low voltage winding of a step-down transformer.

in the hoses using the usual high operating temperature resistance wire, owing to the small cross section of the wire, the conductor was weakened, and soon fractured; and even in the thicker low voltage heating conductors, as there was only one conductor, these were also unreliable owing to their liability to fracture under mechanical stress during use. In the flexible metal tubing, in addition to the necessity of using return conductors, with their disadvantage of unavoidably fouling adjacent objects, these had the further disadvantage that, owing to the varying contact areas between the adjacent turns or articulations resulting from moving the hose from time to time and so changing its curvature, the resistance of the hose was always changing, so that effective control of the heat generated was not possible.

The object of the present invention is to provide a form of flexible electrically heated hose of the kind referred to which will have a constant resistance and thus ensure a uniform heat input, without risk of shock to the operator, and at the same time possess a mechanical robustness which will stand up to all the normal hard wear and tear to which such a hose is necessarily subjected, without risk of fracture.

According to the invention, the conductor means consist in metallic braiding which forms part of the structure of the hose.

Owing to the large cross-sectional area resulting from the multiplicity of wires or strips of which the braiding is made, the amount of heat required is distributed over this large area, so that uniform heating of the braiding is effected at a temperature only a little above that required for the hose. Hence conductor means are provided which are able to withstand the passage of high currents without risk of overheating and burning out; and, in view of the low voltage of the current, without risk of shock to the operator. Again, the flexing of the hose does not vary the resistance of the braided conductor means for the reason that its Wires or strips are connected in parallel. Further, the braiding imparts the requisite mechanical "ice strength to the hose, and so renders it capable of very hard usage without risk of fracture.

Where a single hose only is to be used, two braidings insulated from each other are applied, the ends of the braiding at one end of the 'hoseare connected, for example by sweating, to a ferrule while the other ends of the braiding are respectively connected to the ends of the secondary winding of the transformer. The single form of hose lends itself for spraying with hot water, for example where the spray has to be applied at a distance from the water supply.

Where two hoses are to be'used, as in the spraying of a substance, one braiding only need be used, the braidings on the two hoses being connected at one end, for example by the metal portion of the spraying gun, while at their other ends the braidings are connected to the ends of the secondary winding of the transformer. In this double hose form, the air in the one hose is also heated and so helps to maintain the liquid condition of the coating substance as it is sprayed.

The invention will now be described by way of example with reference to the accompanying semi-diagrammatic drawings which show devices for spraying a normally solid coating substance at ambient temperature.

In the drawings:

Fig. 1 shows an arrangement in which the coating material hose incorporates two conductors in the form of two coaxial braided sleeves.

Fig. 2 is a cross section on an enlarged scale of the hose showing its electrical connections.

Fig. 3 shows an arrangement in which the coating material hose and the air hose each incorporates a single conductor in the form of a single braided sleeve.

Fig. 4 is a cross section on an enlarged scale of the two hoses of Fig. 3 with the electrical connections.

Referring to Figs. 1 and 2, the coating substance is placed in a container 1 which is surrounded by a drum heater 2 according to that described in British Patent No. 713,653 and shown diagrammatically in chain lines. The drum heater is thermostatically adjusted so that the coating substance is raised to the required temperature. The compressed air is introduced through an inlet 3 at the top of the container 1 according to normal practice so as to force the now liquid substance through a hose 4 having its outer end connected by means of a union nut 5 to a spraying gun 6, the hose 4 incorporating two coaxial sleeves of braided electrical resistance metal, 7, 8 insulated from each other. The ends of the braidings adjacent the gun 6 are electrically united by clips 7a, lb on each braiding connected by a strip 9 riveted to the strips, while the inner ends of the braidings are respectively connected through clips '71), 8b to the ends of the low voltage secondary winding 10a of a step-down transformer 10 whose primary circuit is controlled by a switch 11. The spraying gun 6 has its air inlet connected by the usual hose 12 to an air supply (not shown). The coating substance is thus maintained at the desired temperature and therefore liquid condition right up to the gun, so that spraying thereof may be carried out in the normal way. An additional advantage deriving from the use of two coaxial sleeves is that the heat gradient from the outer to the inner portion of the hose wall is not so steep as with a single sleeve, so that the thermal stresses on the hose Wall are reduced.

By connecting the mid-point of the secondary winding to earth as shown in chain line at 10b, in Fig. 2, the gun which is connected to the mid-point of the secondary output, will have no potential to earth, so that it may be laid with safety on earthed surfaces such as a ships hull.

'In the form shown in Fig. 3 the coating substance flows through a single braided hose 13 Whose braid 14 has its one end connected to one terminal of the secondary winding 15a of a step=down transformer 15. The spraying gun 6 has its air inlet. connected to a second hose 16 with which is incorporated a single braided heating conductor 17, the outer end of which is connected to the gun 6 and its inne e d to. the other terminal of the transformer secondary winding 15a. The braidings 14 and 17 are thus onnected through the. gun 6. The. coating substance and the air are thus maintained at the desired temperature until the former is actually sprayed.

If desired the compressed air may be hrs-heated p r to passing through the hose 16, so that the air in the compresse air hose-Which is already heated by its conductor -is maintained at the desired temperature. as it emerges from he pray un! The material of the hose may be rubber or polyvinyl chloride or any known flexible plastic capable of withs nding the necessary tempera ures.-

Qther uses may be tov conduct high temperature fluids without the use of lagging; the use in refrigerators for conveying defrost or other Water from the refrigerator without freezing.

I claim:

1. Flexible hose comprising a hollow tubular structure, wherein the hose structurally includes metallic braiding in the wall thereof forming an electrical conductor adapted to be connected o a source of low-voltage electrical supply, such as the secondary winding of a step-down transfermenwherehy any desired wattage may be introduced into the said conductor; said conductor comprising a pair of electrically insulated braidings in the wall of the hose, means at one end of the pair of braidings electrically connecting the pair, and means at the other end of the pair of braidings for respectively connecting same to the said ends of the secondary winding of said transformer.

In a flexible 1 9 .6. 8 set fQl'th in claim 1, said hose being formed of separate sections each carrying one said braiding, the braidings on the two sections being electrically connected at one end, While the other ends of the braidings are respectively connected to the ends of the secondary Winding of the transformer.

References Cited in the file of this patent UNITED STATES PATENTS

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US926695 *Feb 6, 1909Jun 29, 1909William Robert Salmon FrostVulcanizing apparatus for tire tubes or covers.
US964722 *Dec 28, 1905Jul 19, 1910Us Graphotype CompanyApparatus for casting molten material.
US1105795 *May 23, 1913Aug 4, 1914White S Dental Mfg CoFlexible tubing.
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US1575152 *May 22, 1925Mar 2, 1926Di Battista CharlesSpray application of coating compositions
US1733250 *Nov 6, 1925Oct 29, 1929Nat Aniline And Chemical Co InElectrical heating
US1809714 *Apr 1, 1929Jun 9, 1931Mathews Carl RaymondHeated water hose for filling stations
US2529914 *Jun 22, 1950Nov 14, 1950Denison Mattress FactoryElectrical heating element
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2809268 *Jun 18, 1956Oct 8, 1957Heron Andrew GeorgeFlexible electrically heated hoses
US2883513 *Nov 21, 1957Apr 21, 1959Resistoflex CorpHeated hose assembly
US3001054 *Aug 1, 1958Sep 19, 1961Gen ElectricHeating panel having a plurality of current paths
US3022412 *Sep 26, 1958Feb 20, 1962Goodyear Tire & RubberDeicer
US3057694 *Dec 15, 1958Oct 9, 1962Milton KesslerApparatus for raising sunken ships
US3091205 *Aug 16, 1957May 28, 1963William WatsonMethod of raising sunken vessels
US3141955 *Apr 12, 1962Jul 21, 1964Culpepper Abner ADevice for effecting water-flow from a roof or the like
US3143641 *Sep 25, 1962Aug 4, 1964Gen ElectricWaterproof heating pad
US3298371 *Feb 11, 1965Jan 17, 1967Arnold S J LeeFreezing probe for the treatment of tissue, especially in neurosurgery
US4176662 *Jun 17, 1977Dec 4, 1979The United States Of America As Represented By The Administrator Of The National Aeronautics And Space AdministrationApparatus for endoscopic examination
US4352007 *Oct 22, 1980Sep 28, 1982Nordson CorporationHot melt multi-section hose heating system
US4575617 *Apr 12, 1984Mar 11, 1986CooperheatHeat tracing tape and power control system
US5394507 *May 20, 1993Feb 28, 1995Tokyo Kogyo Boyeki Shokai, Ltd.Heated tube with a braided electric heater
US6148147 *Sep 4, 1998Nov 14, 2000Northrop Grumman CorporationResin supply hose with removable core
US7228067 *Oct 29, 2001Jun 5, 2007Thermo Finnigan Italia S.P.A.Chromatography column assembly with woven tubular mesh heater element
US8455800Sep 11, 2008Jun 4, 2013Graco Minnesota Inc.Helix heated hose
US20070176418 *Jun 15, 2005Aug 2, 2007Volvo Lastvagnar AbElectrically heatable coupling and an encased fluid hose with an electrically heatable coupling
US20100237061 *Sep 11, 2008Sep 23, 2010Tix Joseph EHelix heated hose
US20140361099 *May 5, 2014Dec 11, 2014Finishing Brands Holdings Inc.System and Method for Thermal Control of Flow Through a Conduit
WO2004078357A2 *Mar 4, 2004Sep 16, 2004Der Walt Jacobus Gert VanA spray apparatus and method
WO2004078357A3 *Mar 4, 2004Oct 14, 2004Ludrick Johannes BarnardA spray apparatus and method
WO2005124219A1 *Jun 15, 2005Dec 29, 2005Volvo Lastvagnar AbElectrically heatable coupling and an encased fluid hose with an electrically heatable coupling
Classifications
U.S. Classification219/522, 219/528, 392/472, 219/541, 219/544, 392/478
International ClassificationF16L53/00, B05B7/16, B29D23/00
Cooperative ClassificationB29D23/001, B29K2021/00, B05B7/164, F16L53/005
European ClassificationB29D23/00T, B05B7/16B1H, F16L53/00B6