Abstract:
The present invention is an electrical extensible hose that includes an outer shell, an inner core and at least one helical wire, which acts like a skeleton. In the present invention one implemented an additional wire that was conductive. The outer shell and inner core of the present invention may be bonded together via heat fusion. The helical wire is attached to the inner core via heat fusion. The helical wire supports the outer shell and inner core so as to form a tube. The outer shell and the inner core have a portion that forms an angular fold and have a portion that remains fixed. The second wire is attached at a point below the fixed portion of the electrical stretch hose so as to allow for maximum constriction caused by the shrinkable force created by the helical wire, thus increasing the stretch ratio of the hose.

Description:
FIELD OF INVENTION 
   The present invention relates to stretch hoses, in particular stretch hoses that are wire reinforced with at least one current carrying wire, which is useful for a vacuum cleaner, vacuuming systems and the like. 
   BACKGROUND OF THE INVENTION 
   A hose is a hollow tube designed to carry fluids from one location to another. Hoses are generally cylindrical in shape having a generally circular cross section. Hoses are used in a variety of different applications. Specific applications include:
         A garden hose is used to water plants in a garden or lawn, or to convey water to a sprinkler for the same purpose.   A fire hose is used by firefighters to convey water to the site of a fire.   Air hoses are used in underwater diving (e.g. scuba diving) to carry air from the surface or to from air tanks.   Vacuum cleaner hoses used for transporting the dirt from the vacuum cleaner head to the vacuum cleaner containment unit.       

   In addition to the vast applications hoses can be used for, they come in a variety of different designs, for example some hoses are flexible, i.e. they stretch, as in the present invention, and others are not. The remainder of the specification, of the present patent application, will discuss the former type of hose, with specific reference made to current carrying flexible hoses. Stretch hoses, are generally wire reinforced, and fall into two broad categories, vacuum only and electrical. The majority of stretch hoses are vacuum only. 
   Exhaust systems, air ventilation systems, lint collection systems, oil mist collector systems, HVAC, and of course vacuum cleaners, are just a few of the systems that may implement a current carrying flexible hose. Current carrying hoses may be used with both low and high voltages. In addition, current carrying vacuum cleaner hoses may be integrated with a vast number of different fittings, depending on the desired use. For example, one may attach a brush for cleaning upholstery, or one may attach a wand for reaching those hard to reach places. 
   Flexible hoses are generally reinforced with a wire helix, this allows the hose to expand and contract when needed, some types of extensible hoses may extend up to four times their compressed length. In addition, the reinforced wire helix gives additional strength to the flexible hose. Flexible hoses are constructed of many different materials, depending on their intended use, such as thermoplastic polyurethane, thermoplastic rubber, and the like. Some flexible hoses are clear, and some are colored, depending on their intended use. Most flexible hoses are lightweight, economical, and have excellent flexibility. In addition, flexible hoses are designed to operate in a variety of different environments and temperature ranges, for example some flexible hoses are designed to operate inside and/or outside and under conditions where the temperature can range from −65F to 200F. 
   A flexible current carrying hose can be seen in U.S. Pat. No. 2,890,264, disclosures of which are hereinafter incorporated by reference, invented by Jack E. Duff, assigned to The Hoover Co. That prior art embodied a means for conducting electricity along the length of a hose so that a suction cleaner may be controlled from one end of the hose or to provide electric current at the end of the hose for operating an electrically actuated device at the hose end. However useful this invention was, there were shortcomings, for example it was difficult to assemble an electrical conductor in the hose wall without impairing the extensibility of the hose. 
   Other prior art such as U.S. Pat. No. 2,998,474, disclosures of which are hereinafter incorporated by reference, invented by Mary C. Pavlic, also assigned to the Hoover Company, improved on the shortcomings of the Duff invention, however there still existed the problem of great pressure loss and high suction resistance. 
   A more recent flexible extensible hose is U.S. Pat. No. 6,024,132, disclosures of which are hereinafter incorporated by reference, invented by Noriaki Fujimoto, assigned to Tiger Polymer Corporation, Osaka, Japan, implemented a bellows hose wall with a spiral reinforcing wire and a covered conductor wire. In Fujimoto the reinforcing wire and conducting wire are adjacent to each other, thus limiting the amount of restriction of the hose in a contracted position. 
   Yet another example of prior art may be seen in United Kingdom Patent 2,322,925, disclosures of which are herein incorporated by reference, assigned to Smiths Industries Public Ltd. Co. In this current carting vacuum cleaner hose the hose assembly also consists of a reinforcing wire  4  and a current carrying wire  5 . In this prior art reinforcing wire  4  may also be used as a current carrying wire if desired. However, this prior art also has some disadvantages, for example the current carrying vacuum cleaner hose has limited extensibility, because of the wire configuration, as seen in  FIG. 2  in that application. 
   OBJECTS OF INVENTION 
   It is therefore an object of the present invention to produce a low cost, easy to manufacture an improved flexible current carrying hose. 
   It is an object of the present invention to provide an improved extensible flexible hose. 
   It is an object of the present invention to produce an improved flexible extensible current carrying hose having at least one conducting wire. 
   It is also an object of the present invention to produce a flexible extensible current carrying hose that has a greater stretch ratio than conventional stretch hoses. 
   It is an object of the present invention to provide a hose that has a higher stretch ratio in the order of 8 to 1 than conventional current carrying stretch hoses. 
   These and other objects of the present invention will become apparent to those skilled in the art from a review from the description provided below. 
   SUMMARY OF INVENTION 
   The present invention includes a thermoplastic outer shell that is bonded to an inner core. The outer shell is a flexible thermoplastic film that is sealed to the inner core. The inner core is also a thermoplastic flexible sheet. 
   The reinforcing wire is generally a helical wire that is sandwiched between the core and the outer shell. Also between the core and the shell there may be at least one current carrying wire. The reinforcing wire may be an electrical conducting wire if desired. The present invention also includes a reinforcing wire that may or may not be a conducting wire, and at least one current carrying wire. The main disadvantage of the prior art electrical conducting hose is that if additional wires are present in the hose, particularly current carrying wires, the stretch ratio would be greatly reduced due to the added volume in the helix, thus limiting how tight the hose could be contracted. The present invention, remedies this disadvantage. The present invention takes optimal advantage of the angular fold of the flexible hose where one side of the fold is essentially fixed and most of the deflection and displacement associated with extending the hose occurs on the other side. Thus, by placing one or more additional wires on the bottom of the fixed side of the fold, where large displacements of the flexible cover are not experienced, they can pass under the outer helix, which allows a much tighter contraction of the helix and therefore a greater stretch ratio. 
   An additional benefit to lowering the additional wires in the hose geometry is a smaller helical diameter for the current carrying wires, thereby reducing materials, weight and cost compared to putting all wires at the same diameter as the helical reinforcement, as in the prior art. 

   
     BRIEF DESCRIPTION OF INVENTION 
       FIG. 1  is an end view of the electrical stretch hose of the present invention in the A-A plane. 
       FIG. 2  is cross-sectional view of the electrical stretch hose of the present invention in the A-A plane. 
       FIG. 3  is a cross-sectional view of the electrical stretch hose of the present invention in the A-A plane magnified 10×. 
       FIG. 4  is a perspective view of the electrical stretch hose of the present invention, with two conducting wires, in a retracted position. 
       FIG. 5  is a perspective view of the electrical stretch hose of the present invention, with two conducting wires, in an extended position. 
       FIG. 6  is a perspective view of the electrical stretch hose of the present invention, with one conducting wire, in an extended position. 
       FIG. 7  is a perspective view of the electrical stretch hose of the present invention, with one conducting wire, in a retracted position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
   There are many methods for continuously forming a reinforced flexible hose, one such method may be seen in U.S. Pat. No. 4,213,811, invented by Marcus Hall, the disclosures of which are herein incorporated by reference. Another method may be seen in U.S. Pat. No. 3,155,559, also invented by Marcus Hall, the disclosures of which are incorporated by reference. One may implement any of the aforementioned methods of forming stretch hoses, or other methods not yet known at this time, the crux of the present invention is not the method of forming the stretch hose, but the unique placement of the reinforcing wire and the current carrying wire. 
   As seen in  FIGS. 3-7 , is the electrical stretch hose  10  of the present invention. Electrical stretch hose  10  includes an outer shell material  20 , an inner core material  30 , a reinforcing helical wire  40 , and a current carrying wire  50 . In other embodiments one may add additional current carrying wires as needed. 
   Directing one&#39;s attention to the drawing marked  FIG. 3 , one can see a cross-sectional view of electrical stretch hose  10 . Electrical stretch hose  10  may be generally cylindrical in shape, as seen in  FIGS. 4-7 , however, one may implement any suitable shape known in the art including, but not limited to a square, rectangle, and the like. Electrical stretch hose  10  may have an outer shell material  20 , as seen in  FIGS. 5 and 6 . Electrical stretch hose  10  may have two open ends, which may be used for attaching electrical hose  10  to the desired device being used, also see in  FIGS. 5 and 6 . Outer shell  20  may be manufactured from a variety of different materials, such as resins, PVC, soft plastics and the like. In the preferred embodiment one implemented a thermoplastic material for outer shell  20 . One may implement any suitable color known in the art including, but not limited to black, red, or the like. Conversely, one may implement a transparent outer shell, if desired. In the preferred embodiment one implemented a black thermoplastic. 
   Again directing one&#39;s attention to  FIG. 3 , electrical stretch hose  10  also includes inner core material  30 . Inner core  30  may be manufactured from any suitable known material in the art including, but not limited to resins, PVC&#39;s, soft plastics and the like. In the preferred embodiment one implemented the same type of thermoplastic material used for outer shell  30 . Inner core  30  and outer shell  20  may be bonded or fused together by any suitable known means in the art including, but not limited to heat fusion, adhesives and the like. In the preferred embodiment one bonded outer shell  20  to inner core  30  via heat fusion. 
   Furthermore, one may use multiple layers of thermoplastic material for outer shell  20  and inner core  30 . For example, one may have a stretch hose with two layers of thermoplastic material bonded together, for outer shell  20 , and three layers of thermoplastic material bonded together, for inner core  30 . The need for more then one layer of material, for either outer shell  20  or inner core  30 , will depend on the desired use of the stretch hose. 
   Electrical stretch hose  10  may also include a helical reinforcing wire  40 . Helical wire  40  is the skeleton of electrical stretch hose  10 . Helical wire  40  may be manufactured from any suitable known material in the art, including, but not limited to metal, metal alloy, hard plastic, and the like. In the preferred embodiment one implemented an insulated copper wire. Insulation  41  may have an inner diameter so as to be able to cover helical wire  40 , as seen in  FIG. 3 . Insulation  41  may have outer circumferential surface  42  and inner circumferential surface  42   a . This type of wire was preferred because one desired helical wire  40  to be a current carrying wire. One could however, implement a helical wire made out of plastic, PVC, or any other non-conductive material. One key attribute of helical wire  40  is that it must be able to expand and contract, like a helical spring. Another key attribute of helical wire  40  is that it must be able to support outer shell  20  and inner core  30 . Helical wire  40  may be attached to inner core material  30  by any known suitable means in the art including but not limited to heat fusion or welding and adhesion with adhesives. In the preferred embodiment one attached outer surface  42  of insulation  41  of insulated helical wire  40  to inner core material  30  via heat fusion, as seen in  FIG. 3 . In another type of embodiment one could have sandwiched helical wire  40  between inner core material  30  and outer shell material  20 . In yet another embodiment one may implement more then one helical wire, for example one may implement a stretch hose with two helical wires. 
   As mentioned above one may have one helical current carrying wire, or one may have many current carrying wires. In the preferred embodiment one implemented a single current carrying wire, as seen in  FIGS. 6 and 7 . An embodiment with more than one current carrying wire may be seen in  FIGS. 4 and 5 . In this embodiment one implemented two current carrying wires. Other then the number of current carrying wires used the two embodiments of the present invention operate identically. 
   As just mentioned, in addition to having helical wire  40  one may implement a second wire  50 . Second wire  50  may be conductive or non-conductive, depending on the desired application. In the preferred embodiment one implemented a helical current carrying second wire  50 , i.e. conductive. Since helical second wire  50  will be implemented as a current carrying wire, it will be insulated, and as such has insulation  51  along with outer and inner surfaces  52  and  52   a  respectively, as seen in  FIG. 3 . Second wire  50  may be attached to electrical stretch hose  10  by any suitable method known in the art including, but not limited to the methods mentioned above. In the preferred embodiment one sandwiched second wire  50  between outer shell  20  and inner core  30 . One would like to point out that one could have easily attached second wire  50  in the same manner as helical wire  40 . 
   In normal operation when the electrical stretch hose is in a contracted position, as seen in  FIGS. 3 ,  4  and  7 , there will be a plurality of hills  70  and valleys  71 , the number of hills  70  and valleys  71  will depend on the length of the electrical stretch hose desired, i.e. the longer the length the more hills and valleys that will be present. The distance between hills will vary depending on the corresponding shrinkage force of the helical wire implemented and the type of material used for the outer and inner material. Thus, a helical wire with greater shrinkage force will have less distance between adjacent hills. When electrical stretch hose  10  is in a contracted position, second wire  50  will be positioned under and to the right of helical wire  40 , as seen in  FIG. 3 . In addition, a portion  60  of outer shell  20  and inner core  30  will form an angular fold over second wire  50 , as seen in  FIG. 3 . Another portion  61  of outer shell  20  and inner core  30  remains fixed. The angular folding of portion  61  of electrical stretch hose  10  allows for maximum contraction, and thus increases the stretch ratio. When electrical stretch hose  10  is in a stretched position, the distance between the hills and valleys is increased as seen in  FIGS. 5 and 6 . In addition, located in each valley  71  there may be a ridge  71   a . Ridges  71   a  are formed by second wire  50 , as seen in  FIGS. 5 and 6 . Ridge  71   a  cause the material of the stretch hose to fold, when the stretch hose goes from an extended position to a retracted position. Located at the lowest point of each valley  71  may be base portion  71   c . In addition to the hills  70  and valleys  71  located on outer shell  20 , there may be hills  80  and valleys  81  located on inside core  30 , as seen in  FIG. 3 . 
   Drawing one&#39;s attention to  FIGS. 3-7 , one will now discuss the angular fold of the present invention with one current carrying wire in more detail to give the reader a better understanding on how the present invention improves on the prior art electrical stretch hoses, keeping in mind that the angular fold with two current carrying wires is identical. For illustrative purposes helical reinforcing wires  40  are represented by A, B, C and D. A, B, C and D are all aligned along the same central axis, as depicted in  FIG. 3 . Also, current carrying wire  50 , now represented by A′, B′, C′ and D′ are also aligned along the same central axis.  FIG. 3  will be considered one array of the many arrays present in the electrical stretch hose. When the electrical stretch hose of the present invention is in a retracted position, A′ will be located below and between A and B. In addition, B′ will be located between B and C, and so forth. This will continue down the length of the hose, because of the symmetrical configuration of the hose, that is to say each portion on electrical carrying wire will be located below and between two corresponding reinforcing wires in different arrays. When the electrical stretch hose is in an extended position, B′ will be located between A and B, C′ will be located below and between B and C and so forth down the length of the hose, for the foregoing reasons. The reason for this “shift” is because of the positioning of the current carrying wire and the reinforcing wire. In another embodiment one may also have the current carrying wire “shift” across more then one portion of the helical wire. For example, in the preceding example when the stretch hose is in an extended position, C′ may be located between B and C, as previously discussed, however if one desired one could have C′ “shifted” to a position between A and B. The shift of the current carrying wire will depend on needed application of the stretch hose. In prior art the current carrying wire and the reinforcing wire are adjacent to each other, whereas in the present invention the current carrying wire is located in the angular fold. 
   The key feature of the present invention is not the attaching methods of wires  40  and  50  to electrical stretch hose  10 , but rather the positioning of second wire  50  in relation to helical wire  40 . In the present invention second wire  50  must be placed on the bottom of the fixed side of the fold, this is where large displacements of the flexible cover are not experienced, thus allowing second wire  50  to pass under outer helical wire  40  allowing for a much tighter contraction of the helix and therefore a greater stretch ratio. 
   As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense. In the view above it will be seen that several objects of the invention are achieved and other advantageous results attained.