Field of the Invention

This invention finds application in the field of household cleaning accessories and particularly relates to an extensible hose assembly for use in machines for cleaning carpets , floors , moquettes, walls or the like .

Prior art

Many embodiments of cleaning apparatuses and devices are known, for use in both domestic and industrial applications . The core of these machines is the central unit, which generally includes a motor unit coupled to a boiler unit with a tank. The central unit generates a negative pressure to suck in air and liquids to be removed and delivers the cleaning fluid, which is typically steam, but may also be water, a detergent or the like .

The fluid is conveyed to the cleaning tool through suitable hoses . These hoses are preferably telescopic, in such a manner to allow a user to adjust the length of the tool as needed.

The application WO2003/101273 , having the same inventor of the present application, discloses a telescopic hose assembly comprising two pairs of superimposed hoses, the one adapted for suction and the other for delivering a working fluid. Such prior art tube has the drawback of involving a number of fluid tight areas which may become worn and collapse

mechanically, possibly as a result of the operating temperatures and pressures of steam.

From WO2004/028323 , by the same inventor as above hereof, which represents the basis for the preamble of claim 1, a telescopic hose is known which comprises two pairs of telescopically sliding rigid tubular elements, one outside the other, for conveying steam from one source to a working tool .

This arrangement also has a several recognized drawbacks .

In fact this apparatus fluid sealing areas still pose a problem for the mechanical resistance of the whole assembly.

Yet, the special materials employed for the sealing areas cause the fabrication costs to dramatically increase .

Summary of the invention

The obj ect of this invention is to overcome the above mentioned drawbacks, while providing a hose assembly that is practical, cost-effective and most of all efficient .

A particular obj ect is to provide a hose assembly which minimizes fluid sealing areas .

A further obj ect is to provide a cost-effective hose assembly.

These obj ects , as well as others which will be more apparent hereinafter, are fulfilled by an extensible hose assembly according to claim 1 , which comprises : at least one first

conduit, said first conduit being formed by at least one first pair of substantially rigid tubular elements , coupled together in telescopically sliding relationship; at least one second conduit, said second conduit being made from a material adapted to convey a working fluid at a predetermined maximum temperature; first means for connecting an end of said second conduit to a source of said working fluid and means for delivering said working fluid at the opposite end of said second conduit, characterized in that said second conduit is substantially unitary and flexible and is of variably configuration and length to adjust the distance between said opposite ends, said first conduit being external to said second conduit to define a mechanically and thermally protective covering, suitable to be grasped by a user, and to fit length adjustments on said second conduit .

Thanks to this particular arrangement, the hose assembly according to the invention allows to minimize fluid tight areas as compared with prior art hoses, thus resulting more practical, efficient and durable .

Brief Description of the Drawings

Further features and advantages of the invention will be more apparent from the detailed description of a preferred, nonexclusive embodiment of a hose assembly according to the invention, which is described as a non-limiting example with the aid of the annexed drawings , in which:

FIG . 1 is a general diagrammatic view of a particular embodiment of the assembly according to the invention;

FIG. 2 is a partly sectional view of an embodiment of a detail of FIG . 1 in the contracted position;

FIG. 3 is an enlarged view of a detail of FIG. 1;

FIG. 4 is a partly sectional view of the embodiment of FIG. 2 in the expanded position;

FIG. 5 is a partly sectional view of another embodiment of a detail of FIG . 1 in the contracted position;

FIG. 6 is a partly sectional view of the embodiment of FIG. 5 in the expanded position;

FIG . 7 is a partly sectional view of a further embodiment of a detail of FIG. 1 in the contracted position; FIG. 8 is a partly sectional view of the embodiment of FIG . 7 in the expanded position;

FIG. 9 is a general diagrammatic view of yet another embodiment of the assembly according to the invention;

FIG. 10 is a partly sectional view of an embodiment of a detail of FIG. 9 in the contracted position;

FIG . 11 is a partly sectional view of the embodiment of FIG. 10 in the expanded position;

FIG . 12 is a partly sectional view of another embodiment of a detail of FIG . 9 in the contracted position; FIG. 13 is a partly sectional view of the embodiment of FIG . 12 in the expanded position;

FIG. 14 is a partly sectional view of a further embodiment of a detail of FIG. 9 in the contracted position;

FIG. 15 is a partly sectional view of the embodiment of FIG. 14 in the expanded position;

FIG . 16 is an enlarged view of a detail of the assembly according to the invention;

FIG. 17 is an enlarged view of a detail of FIGS . 7 , 8 , 14 and 15; FIG. 18 is an enlarged view of another detail of the assembly according to the invention;

FIG . 19 is an enlarged view of a further detail of the

assembly according to the invention .

Detailed description of a few preferred embodiments

With reference to the above mentioned figures , the hose assembly according to the invention, as particularly shown in FIG. 1, is connecting a source S of working fluid, which may be steam, to means ϋ for delivering the fluid to carpets, floors, moquettes, walls or the like .

The assembly, which is generally designated with numeral 1, comprises at least one first conduit 2 and at least one second conduit 3.

Particularly, the first conduit 2 is composed of a first pair of substantially rigid tubular members 4 , 4 ' , coupled together in telescopically sliding relationship, whereas the second conduit 3 is made of a material adapted to convey a working fluid at a predetermined maximum temperature, and is preferably able to continuously withstand a temperature of at least 100 ⁰ C, i . e . the typical operating temperature of steam. The conduit 3 may obviously also convey hot or cold water, detergents or the like .

Advantageously, this material may be a polymeric material, such as thermoplastic or thermosetting vulcanized rubber, silicone or nylon .

A number of different materials may be used, such as PVC, PP, nylon and generally polymeric materials may be employed for the conduit 2.

First means 6 for connection to the source S are provided at one free end 5 of the second conduit 3, whereas means U are fitted to the opposite free end 5' . In FIG. 1, the very assembly 1 is connected to the unit S by the hose C .

According to the invention, the second conduit 3 is arranged internally of the first conduit 4 and is substantially unitary and flexible, and is of variable configuration and length to adjust the distance 1. between the ends 5, 5' .

Thanks to this basic embodiment, the assembly according to the invention allows to minimize fluid sealing areas as compared with prior art embodiments, and . therefore is more practical, efficient and durable .

A small number of fluid sealing areas involves a smaller number of weak parts in the assembly, and requires less servicing and maintenance operations . A minimized number of such sealing areas also involves a reduced risk of irreversible collapse of the structure at those areas, which are the most stressed by the passage of the hot working fluid.

This provides a substantially cost-effective assembly, due both to its reduced servicing and maintenance operations, and to its use of moderate cost materials .

Advantageously, as particularly shown in FIG. 3, the first outer conduit 2 may be so sized that the tubular intermediate space 7 between the inner wall 8 of this conduit 2 and the outer wall 9 of the second conduit 3 has a predetermined minimum thickness s_, so as to allow a user to grasp with

unprotected hands the outer wall 10 of this conduit 2. Obviously, the thickness j3 may be varied according to the materials that form the conduits 2 and 3.

Suitably, the minimum thickness s_ may be of 1 mm to 50 mm, and is preferably of about 5 mm.

By way of non limiting example, if the first conduit is made of polypropylene and the second conduit is made of nylon, and steam is conveyed therein at about 120 ⁰ C, the thickness s _^ of the air space may be of about 6 mm.

According to a first embodiment, which is particularly shown in FIGS . 2 and 4 , the second conduit 3 may be shaped substantially as a cylindrical spiral, and has an adjustable shape which can vary from its initial length I i and its final length I ₂ .

According to another embodiment, which is particularly shown in FIGS . 5 and 6, the second conduit 3 may be substantially tubular, having a sufficient modulus of elasticity to allow a full extension between the opposite free ends 5 and 5' , at which the conduit 3 will have the length I ₂ . The second conduit 3 actually operates like an elastic tube, expanding and contracting between Ii and I ₂ , to fit the changing positions of the above free ends 5 and 5' . Suitably, the tubular conduit 3 , in this embodiment, may be substantially straight as its total length changes .

In a further embodiment, as shown in FIGS . 7 and 8 , the second conduit 3 may be of the tubular type, with at least two opposed loops 11 and 11' . Such loops will be spaced apart

at a distance d ranging from di and άg, corresponding to the lengths Ii and Ig of the second conduit 3 respectively.

In this latter embodiment, the conduit 2 may include guide means 12 for guiding the loops 11 and/or 11' , to prevent the conduit 2 from being obstructed as it changes its length . As particularly shown in FIG. 16, the means 12 may be provided in the form of partitions 13 and 13' , along which the hose 3 is "forced" to slide, not to accidentally bend on itself .

Advantageously stretching means 14 may be further provided to act on loops 11 and 11' , to bring the conduit 3 back to its initial length I].. As particularly shown in FIG. 17 , the stretching means 14 may be provided in the form of suitable "pulleys" 15 and 15' , which have the function of tensioning the conduit 3 to facilitate its sliding motion inside the conduit 3.

Still suitably, the conduit 3 may have shape control means 16, for maintaining the shape thereof unchanged, as its length changes from lχ_ to Ig.

Preferably, as particularly shown in FIG. 18 , control means 16 may include a constraining retainer wire 17 made of spring steel or nickel steel, which may be spirally wound inside and/or peripherally outside the side wall 9 of the conduit 3. The function of the wire 17 is to help the conduit 3 to get back to its natural shape, once it is unavoidably bent upon mutual sliding of the member 4 and 4 ' .

Advantageously, the assembly may include a third suction conduit 18 of variable length, arranged externally of the

first conduit 2 and substantially parallel thereto . This embodiment of the invention will not only enable to clean carpets , flooring and the like by the steam delivered from the hose 3, but also to suck in the dirt deposited thereon every day, such as dust, hairs or the like .

Preferably, the third conduit 18 may comprise a second pair of mutually sliding rigid telescopic tubular members 19, 19' , similar to the members 4 and 4 ' .

Suitably, as particularly shown in FIG. 9, the conduit 18 may have, at one end, second connecting means 21 for connection thereof to an air suction unit A, usually coupled to the source S and, at an opposite end 22 , an opening 23 for receiving the material sucked in by suitable suction means, which are typically incorporated in device U . In this figure, the connecting means 21 joint the assembly 1 to the unit A by the connection hose C .

It is to be understood that here again the assembly may include the spiral conduit 3 as shown in FIGS . 10 and 11, or a straight tubular conduit as shown in FIGS . 12 and 13 , or also a straight tubular conduit with loops 11 and 11 ' as shown in FIGS . 14 and 15 , with all the features and the advantages discussed above .

In order to lock them against mutual sliding motion, the tubular members of the first pair 4 , 4 ' and/or the second pair 19, 19' may have locking means 24 , to adj ust the assembly 1 to the desired length .

Preferably, as particularly shown in FIG. 19, the locking

means 24 may include a linear slider 25, which is fitted onto one of the tubular elements of the pairs 4 , 4 ' or 19, 19 ' , a stop member 26, which is operable by said linear slider 25 and engageable in a plurality of substantially equispaced recesses 27 , evenly arranged on the other of said elements . The locking means may be supplemented by appropriate safety means 28.

From the foregoing, it appear that the assembly of the invention achieves the intended obj ects and particularly meets the requirement of being practical and efficient, while minimizing the number of fluid sealing areas .

Thanks to the use of a unitary and flexible conduit 3, the above mentioned weak critical points may be reduced to a number of two, at the inlet and outlet of the conduit 3.

The assembly of this invention is susceptible to a numerous modifications and changes, all falling within the inventive scope of the invention as disclosed in the appended claims . All the details may be replaced by other technically equivalent parts, and the materials may vary depending on different needs , without departing from the scope of the invention .

While the assembly has been described with particular reference to the accompanying figures, the numerals referred to in the disclosure and claims are only used for the sake of a better intelligence of the invention and shall not be intended to limit in any manner the claimed scope of the invention .