CA1086247A - Electroconductive hose for cleaner - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A hose for cleaners comprising a bellows-shaped hose main body and two reinforcing synthetic resin elements arranged side by side axially of the hose and helically wound on and attached to the inner surface of the hose main body.
Each of the reinforcing helical elements has embedded therein a conductor comprising a hard steel wire and a plurality of thin copper wires provided on the outer periphery of the hard steel wire and extending longitudinally thereof.

Description

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TI~L~ 0~ ~H~ iTIOli ~ECTROCONDUCTIV~ HOSE FOR CL~ANER
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~ACKGROUND 0~ ~HE I~E~TION
This invention relates to a hose for use in c'eaners - 5 of the power nozzle type, and more particularly to improvements in a cleaner hose which is electrically conductive and which has embedded therein helical conductors for electrically connecting a 3witch for a drive device on the forward end of - -the hose to a main ~witch mounted on a hose gripping portion and po~itioned closer to the main body of a cleaner.
Conductive cleaner hoses of this type heretofore known include tho~e in which copper wires helically wound on and attached to the inner surface of a bellows-shaped hose wall for reinforc~ng the hose serve also as conductors. With such hoses, reinforcing copper wire conductors of large diameter having a sufficient load capacity to pass great current, if used, will seriously impair properties such as stretchability and flexibility which are essentially required of the hoses.
Conversely the use of copper wires of small diameter as - 20 conductors and reinforcing elements 90 as to ensure improved ; ~tretchability and higher flexibility entail~ a voltage drop, rendering the copper wires unable to pas~ great current, and further involves the drawback that the copper wires fail to give sufficient strength ~or the hose to retain its 3hape.
Consequently when the hose is repeatedly subjected to external forces as by being trampled, stretched or bent during use, ' 1 :

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~ 086247 the copper wires will break and become unable to provide reinforcement for the hose and to serve as a conductor early.
Another cleaner hose is known which comprises a bellows-shaped hose main body and two reinforcing elements of thermoplastic elastic material arranged side by side and ~ helically wound around and attached to the outer surface of the hose main body, each of the reinforcing helical element~
having embedded therein a conductor composed of a hard steel wire and twisted copper wire~ wound around the hard steel wire. The conductor embedded in the helical element has ~
relatively large diameter and therefore has the advantage of being capable of passing greater current than those of the conventional hoses described. However, the conductor-incorporating reinforcing helical elements which are arranged on the outer surface of the hose are liable to wear away early from outside to expose the conductors since the ho~e is inuariably dragged during the uæe of the cleaner. As a result, troubles such as a short circuit or electric shock are very likely to develop. Moreover,`the reinforcing elements of increased cross sectional area required have the drawback of rendering the hose less stretchable and flexible.

SUMMARY OE THE INVENTION
The main ob~ect of thi~ invention 18 to eliminate the drawbacks inherent in the conventional conductive cleaner hoses described above.
To fulfil the above object, the pre~ent invention provides a conductive hose for cleaners comprising a bellows-shaped hose main body and two reinforcing synthetic resin elements arranged side by side axially of the hose and helically wound on and attached to the inner surface of the hose main body, the cleaner hose being characterized in that each of the reinforcing helical elements has embedded therein a conductor comprising a hard steel wire and a plurality of thin copper wires provided on the outer periphery of the hard steel wire and extending longitudinally thereof.
The conductor embedded in each of the two reinforcing helical elements is composed of a hard steel wire and a plurality of copper wires provided on the outer periphery of the hard steel wire and extending longitudinally thereof.
With this construction, a conductor having a large diameter relative to the cross seCtion of the reinforcing helical element and therefore possessing a high conductivity can be embedded in the element for the passage of great current, whereas the reinforcing helical elements so constructed impart sufficient shape-retaining strength to the hose without giving substantially detrimental effects on the stretchability and flexibility of the hose itself. ~ecause the conductors are embedded in the reinforcing elements, they can be fully protected from external forces which will frequently act thereon when the hose i9 stretched or bent during use.
Thus the hose retains a satisfactory conductivity over a prolonged period of time. hdditionally, the conductor-incorporating reinforcing helical elements, which are helically ., ~, . . . . .
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wound along and attached to the inner surface of the hose main body, render the hose serviceable over a grsatly lengthened period of time before the hose is worn away to expose the conductors by being dragged during the use of the cleaner. Accordingly the cleaner hose in its entirety - retains a stable conductivity during its prolonged life free of troubles such as a short circuit or electric shoc~.

BRIEF DESCRIPTIO~ OF THE DRA'~INGS
Fig. 1 is a side elevation partly broken away and showing a conductive cleaner hose embodying this invention;
Fig. 2 is a fragmentary enlarged side elevation in vertical section showing the same; and Figs. 3 to 5 are enlarged perspective views partly broken away and each.showing a reinforcing helical element.

15D~SCRIPTIO~ OF TH~ PREFERRED EMBODIMENTS
Embodiments of this invention will be described below in detail. Fig. 1 shows a cleaner hose comprising a bellows-shaped hose main body 1 made of soft synthetic resin and - two reinforcing elements 2 of hard synthetic resin arranged side by side a2ially of the hose and helically wound on and attached to the inner surface of the hose main body.
As shown in Fig. 2, each of the reinforclng helical elements

2 has embedded therein a conductor 5 comprising a hard steel wire 3 and a plurality of thin copper wires 4 provided on the outer periphery of the hard steel wire 3 and extending .. , . -. . .

, -1~)8~iZ47 longitudinally thereof. The two conductors 5 serve as a positive conductor and a negative conductor for electrically connecting a switch for a drive device on the forward end of the hose to a main switch mounted on a hose gripping portion and positioned closer to the main body of a cleaner. Piano wires are useful as the hard steel wires 3.
The hard steel wire 3 and the plurality of thin copper wires 4 may be arranged as shown in Figs. 3, 4 or 5 to form the conductor 5. With reference to Fig. 3, the plurality of thin copper wire~ 4 are arranged in parallel or substantially in parallel to one another over the entire outer periphery ---of the hard steel wire 3. Fig. 4 show~ the plurality of thin copper wires 4 in the form of a bundle extending along part of the outer periphery of the hard steel wire 3.
~he plurality of thin copper wires 4 shown in Fig. 5 are twisted together in the form of a bundle and provided along part of the outer periphery of the hard steel wire 3.
In any of these arrangements, the copper wires 4 must be disposed along the hard steel wire 3 longitudinally thereof.

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Claims (5)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An electroconductive hose for cleaners comprising a bellows-shaped hose main body (1) and two reinforcing synthetic resin elements (2) arranged side by side axially of the hose and helically wound on and attached to the inner surface of the hose main body (1), each of the reinforcing helical elements (2) having embedded therein a conductor (5) comprising a hard steel wire (3) and a plurality of thin copper wires (4) provided on the outer periphery of the hard steel wire (3) and extending longitudinally thereof.

2. A hose as defined in claim 1 wherein the plurality of thin copper wires (4) are arranged in parallel or substan-tially in parallel to one another over the entire outer periphery of the hard steel wire (3).

3. A hose as defined in claim 1 wherein the plurality of thin copper wires (4) are in the form of a bundle extending along part of the outer periphery of the hard steel wire (3).

4. A hose as defined in claim 1 wherein the plurality of thin copper wires (4) are twisted together in the form of a bundle extending along part of the outer periphery of the hard steel wire (3).

5. A hose as defined in claim 3 wherein the hard steel wire (3) is a piano wire.