This invention relates to a cylinder-type vacuum cleaner, wherein a flexible hose having a cleaning tool at one end at its other end engages a suction socket in the body of the cleaner.

Such cleaners are used often by maintenance engineers in a compact version as within a carrying case. A problem frequently arises that a considerable static electrical charge can build up on the cleaning tool and the suction hose, particularly when used for cleaning equipment which itself builds up static charges, or for cleaning powdery wastes which themselves carry a charge, for example copier toner.

The invention therefore proposes a cylinder-type vacuum cleaner having a flexible hose with a cleaning tool at its one end which at its other end engages a suction socket in the body of the cleaner , wherein an electrical conductor connects the chassis of the vacuum pump motor to the flexible hose for dissipating static electricity at the hose.

Since the powder or dust may carry an electrical charge and then accumulate in a waste bag within the cleaner, it is preferably arranged that the waste bag also makes electrical contact with the electrical conductor. For this purpose, the conductor may be relatively wide in extent, for example an electrically conductive tape stuck within the body of the cleaner, where the waste bag is housed.

In order further to improve the effectiveness and

simplicity of use, the waste bag which lies within just the suction socket may be mounted on a panel forming a wall of the cleaner, the panel being hinged to give access to the waste bag for removal and replacement.

In order that the invention shall be clearly understood an exemplary embodiment thereof will now be described with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a vacuum cleaner according to the invention with its parts packed within its carrying-case?

Figure 2 shows a longitudinal section through the middle of the body of the cleaner, with the lid removed; and

Figure 3 shows a similar view to Figure 2, but with the waste bag in its pivoted axis position-up.

A vacuum cleaner has a body portion 10 with a lid 11 hinged thereto. The lid has a handle (not shown) on its top surface. A number of tools for connection to the cleaner are mounted for retention within the lid 11. A small control panel 12 has an on/off switch and an i indicator light. On the top surface of the body portion 10, suitable spaced members and projections provide locations for storing a flexible hose 13 and the electric power cable 14. At the other end of the body portion 10 is a suction inlet which cannot be seen in this illustration. The body portion 10 and lid 11 are of injection moulded plastics material and are prone to accumulating relatively large static electricity charges.

Turning now to Figure 2, the body section 10 is shown simplified, in longitudinal section. It can be seen to be divided into hollow chambers 16, 17 by a wall 18 which includes a grill 19, preferably with a filter, so that it is air-permeable. Chamber 16 contains a vacuum pump driven by an electric motor 21, and chamber 17 contains the dust-collecting means. The latter comprises an outer fabric bag 22 mounted removably within an annular frame 23. Within the outer fabric bag 22 is positioned an inner paper bag 24 which has a cardboard carrier member 25 which likewise locates in the frame 23.

The chambers, 16, 17 are closed respectively by a fixed panel 30 and a movable panel 31 which is hinged at 32 approximately at the point where the wall 18 divides the body portion. The hinge 32 may be on the panel 30 or the sides of the body portion 10. The frame 23 is in turn hinged at 33 to the movable panel 31. The top surface of the panels 30, 31 carry the various posts and other formations for holding the hose 30 and the power cable 14.

The end wall 35 of the body portion 10 has a circular opening delimited by a socket member 36, and an electrical conductor 37 extends from the socket member 36 to the pump and motor 21. In use, the flexible hose 13 plugs into the socket member 36 and then directly through an aperture in the cardboard member 25 into the paper inner waste-collecting bag.

It will be seen that any tendency for static electricity to build up on the hose 13 or its tools is dissipated by virtue of the electrical connection 37 leading to the motor which in turn is earthed. For

this action to be most effective, the hose 13, its plug end and the socket member 36 are preferably made of materials which conduct or partially conduct electricity, such as a plastics composition containing a carbon black filler. This will prevent users of the vacuum cleaner from receiving static electric shocks.

Figure 3 illustrates the simple way of removing and replacing the dust-collecting bags 22, 24. The closure panel 31 is pivoted at the hinge 32. In the raised position shown in Figure 3, the cardboard member 25 can easily be grasped for removal and replacement. When lowered again, the aperture in the cardboard member 25 comes automatically to lie adjacent to the socket member 36, and simultaneously the cloth bag 22 makes contact with the electrical conductor 37 so as to dissipate any static collecting in the bag or its contents. For this purpose, the conductor 37 is made with a width of about 1 to 5 cms. in the form of an adhesive tape carrying a conductive surface, for example of aluminium. As shown the annular frame 23 in the raised position locates within the top edge of end wall 35 to hold the panel 31 in its opened position.

Although not illustrated, the socket member 36 is provided with a closure device to ensure that dust collected cannot escape again. Earlier cleaners have had a removable bung. The present device is provided with a pivoting shutter within the end wall 35 with an external actuating knob. Before the hose 13 is plugged in, the shutter is swung away to clear the opening, and is swung back to close it after use.

In a further version, the shutter is sprung and arranged to swing closed as the hose 13 is withdrawn, avoiding the possibility that the user forgets to close it. It must be opened again by hand.