GB1569578A

GB1569578A - Flexible suction hose for an electrically powered vacuum cleaner

Info

Publication number: GB1569578A
Application number: GB5338876A
Authority: GB
Original assignee: Progress Elektrogeraete Mauz and Pfeiffer GmbH and Co
Current assignee: Progress Elektrogeraete Mauz and Pfeiffer GmbH and Co
Priority date: 1975-12-23
Filing date: 1976-12-21
Publication date: 1980-06-18
Also published as: FR2336110A1; DE7541088U; FR2336110B3

Description

(54) A FLEXIBLE SUCTION HOSE FOR AN ELECTRICALLY POWERED VACUUM CLEANER (71) We, PROGRESS - ELEKTROGERATE MAUZ & PFEIFFER GmbH. & Co., a Kommanditgesellschaft of the Federal Republic of Germany, of 25 Griegstrasse, 7000 Stuttgart 1, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a flexible suction hose for an electrically.powered vacuurn cleaner, the hose comprising a flexible inner hose, a flexible outer sheath on the inner hose, and an electric lead between hose and sheath.

On vacuum cleaners having a housing which rests on the floor and which is connected to a suction tool through a suction hose, it is known, see for example U.K.

Specification No. 897,717, to locate the electric lead connecting a current supply to the suction tool between the inner hose and outer sheath and to provide plugs at both ends of such leads. So as not to inhibit flexibility the electric lead can be formed helically.

The production of such a lead is elaborate and expensive. Due to the helical form of this lead, which has an external diameter of not less than 12 mm for functional reasons and because of the necessary insulation, there can furthermore be seen on the suction a very conspicuous thickening. The flexibility of the lead is also impaired.

U.K. Specification 1,160,805 shows a suction hose having an inner hose, outer sheath and electric lead but with the lead running in a groove in the inner hose. This gives rise to a rather complex section and the need to provide a closure for the groove and the need for a specific operation to locate the lead in the groove all of which give rise to increased complexity and cost in manufacture.

The invention provides a flexible suction hose for an electrically-powered vacuum cleaner comprising a flexible inner hose with a uniform circular cross-section and smooth external contour with a flexible outer sheath on the inner hose and a meandering electric lead between inner hose and outer sheath in which the thickness of the electric lead is greater than the thickness of the sheath in which the lead, when viewed in the axial direction of the hose, is arched so as to conform to the surface of the inner hose and in which the sheath acts to hold the lead in position.

With a suction hose according to the invention the electric lead does not significantly inhibit the flexing of the hose and does not conspicuously thicken the hose.

Manufacture tends to be simple and inexpensive and the electric lead is held securely in position at all times.

The invention will now be described further by way of example only, with reference to the accompanying drawings, in which : - Fig. 1 is a plan view of a suction hose according to the invention; Fig. 2 shows a pre-moulded electric lead of zig-zag meandering form for use in the hose of Fig. 1; Fig. 3 shows a pre-moulded electric lead which may be used as an alternative to the zig-zag form; Fig. 4 is a transverse section of the hose taken on line IV-IV of Fig. 1; Fig. 5 is a view corresponding to Fig. 4 and shows a modified electric lead; and Fig. 6 is a transverse section through the hose taken on the line VI-VI of Fig. 1.

Referring now to the drawings, the hose has a flexible, rubber inner hose or tube 1 with a uniform circular cross-section and smooth external contour, a braided outer sheath 2 on the tube, and an electric lead 3, between the tube and sheath. The lead is shown to have a zig-zag meandering form in Figs. 1 and 2 and a sinusoidal form in Fig. 3. The lead may have other meandering forms. The lead is thicker than the sheath and is arched so that it coincides with the surface of the inner hose or tube 1.

The tube 1 is reinforced at its internal surface in manner known per se by a helical reinforcing spring 6 (Figs. 4 to 6), which imparts to the tube the required resistance to bending and compression. The reinforcing spring 6 may exist at the internal surface of the tube 1 or may be embedded in such internal surface.

In Figs. 4 and 6 it is seen that spaces 8 exist between tube, sheath and lead. To ensure that the braided sheath conforms closely with the shape of the tube 1 and on the lead 3, it is preferred that the lead 3 has a shape so that no significant spaces 8 exist. To this end in the embodiment shown in Fig. 5, the insulation of the lead is widened by lateral wings 7, which are tapered.

In order to reduce, as far as possible, any thickening of the suction hose by the electric lead, the lead is, as stated above, arched as at 9 (Fig. 6) so that it conforms to the cylindrical surface of the tube 1. The "amplitude" of the zig-zag or sinusoidal path of the lead in the peripheral direction of the tube is equal to substantially the radius of the tube 1.

The two ends of the suction hose and the ends of the electric lead are provided in known manner with connecting elements for the appliances at one end and for the suction tool at the other end.

WHAT WE CLAIM IS:- 1. A flexible suction hose for an electrically-powered vacuum cleaner comprising a flexible inner hose with a uniform circular cross-section and smooth external contour with a flexible outer sheath on the inner hose and a meandering electric lead between the inner hose and outer sheath in which the thickness of the electric lead is greater than the thickness of the sheath, in which the lead, when viewed in the axial direction of the hose, is arched so as to conform to the surface of the inner hose, and in which the sheath acts to hold the lead in position.

2. A hose as claimed in claim 1, in which the lead meanders with an amplitude substantially equal to the radius of the hose.

3. A hose as claimed in claim 1 or 2, in which the lead meanders in a regular zig-zag form.

4. A hose as claimed in claim 1 or 2, in which the lead meanders in a regular sine-wave form.

5. A hose as claimed in any preceding claim in which the lead has a cross-sectional shape such that no significant spaces exist between hose, sheath and lead.

6. A hose as claimed in claim 1, substantially as hereinbefore described with reference to Figs. 1, 2, 4 and 6 of the accompanying drawings or as modified as shown in Fig. 3.

7. A hose as claimed in claim 5, substantially as hereinbefore described with reference to Figs. 1, 2 and 5 of the accompanying drawings or as modified as shown in Fig. 3. -

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. and is arched so that it coincides with the surface of the inner hose or tube 1. The tube 1 is reinforced at its internal surface in manner known per se by a helical reinforcing spring 6 (Figs. 4 to 6), which imparts to the tube the required resistance to bending and compression. The reinforcing spring 6 may exist at the internal surface of the tube 1 or may be embedded in such internal surface. In Figs. 4 and 6 it is seen that spaces 8 exist between tube, sheath and lead. To ensure that the braided sheath conforms closely with the shape of the tube 1 and on the lead 3, it is preferred that the lead 3 has a shape so that no significant spaces 8 exist. To this end in the embodiment shown in Fig. 5, the insulation of the lead is widened by lateral wings 7, which are tapered. In order to reduce, as far as possible, any thickening of the suction hose by the electric lead, the lead is, as stated above, arched as at 9 (Fig. 6) so that it conforms to the cylindrical surface of the tube 1. The "amplitude" of the zig-zag or sinusoidal path of the lead in the peripheral direction of the tube is equal to substantially the radius of the tube 1. The two ends of the suction hose and the ends of the electric lead are provided in known manner with connecting elements for the appliances at one end and for the suction tool at the other end. WHAT WE CLAIM IS:-

1. A flexible suction hose for an electrically-powered vacuum cleaner comprising a flexible inner hose with a uniform circular cross-section and smooth external contour with a flexible outer sheath on the inner hose and a meandering electric lead between the inner hose and outer sheath in which the thickness of the electric lead is greater than the thickness of the sheath, in which the lead, when viewed in the axial direction of the hose, is arched so as to conform to the surface of the inner hose, and in which the sheath acts to hold the lead in position.