GB2633362A - Floor tool for vacuum cleaner - Google Patents

Abstract

A floor tool for a vacuum cleaning machine comprises an upper housing having a front region, two opposed side regions, and a rear region, wherein an underside of the tool comprises a floor-facing base portion, the base portion being provided with a transversely extending upwardly recessed channel 25, wherein the channel is provided with an exit aperture which feeds into a suction conduit 18 for communicating with suction generating means in the vacuum cleaning machine, the arrangement being such that in use fluid is drawn from the tool underside into the recessed channel and out of the exit aperture into the suction conduit, characterised in that the housing is formed with a plurality of elongate ducts 28, 29 which each extend from an exterior of the housing into the channel, so that in use air is ducted via the housing into the channel so as to form an air jet projecting from each duct. Each duct may be oriented so as to project air onto the underlying floor surface under the channel. Each duct preferably has a tapered profile so as to accelerate ducted air into the channel.

Description

Floor tool for vacuum cleaner The present invention concerns the field of floor treatment machines and relates in particular to vacuum cleaners, or cleaners which include floor suction devices as a main or ancillary functions.

The present invention relates to a floor tool which is attached to (or integrated in) a vacuum cleaner in order to clean carpets, rugs, and hard flooring etc. In a typical arrangement the floor tool is attached to a hollow wand that is in fluid communication with a suction turbine by means of a flexible hose. The suction turbine may be disposed within a remote canister or an upright vacuum cleaner fed by the flexible 113 hose. The suction turbine draws air into the canister or upright cleaner for collection of entrained detritus and subsequent disposal.

Typically vacuum cleaner floor tools have a base portion provided with an air channel or vacuum slot defined by a recess along the transverse width of the floor tool. The recess opens onto the floor, and has an upper aperture which feeds into the wand, is so that air and entrained dust may be drawn up onto the recess thence to the wand via the aperture. The recess may accommodate a horizontal rotating brush bar which may be motor-driven so as to agitate the underlying floor surface.

The base portion or underside of the floor tool supports the floor tool on a given surface to be cleaned. The floor tool may be adapted to slide over a floor or carpet surface, or may be provided with support wheels to facilitate travel over a floor surface, whilst maintaining the base portion at an optimum cleaning height or disposition. The floor tool may be rendered steerable by means of a first wand pivot which permits up-down movement through an arc, and side-to side pivoting via rotation of the wand with respect to the floor tool, so that twisting of the wand upper portion distal from the floor tool moves the tool left or right so as to follow a respective left or right arc.

In use, the floor tool moves over the carpet, rug or hard floor with air being drawn into the vacuum slot via the gap between the front underside of the floor tool base portion. This restricted path accelerates the air as it is drawn into the slot/channel, thereby to entraining dust, debris etc present in the carpet or on the floor. A problem with these floor tools is that the base portion may be sucked down onto the floor or carpet by the Bernoulli effect. This prevents ease of travel of the floor tool over the surface to be cleaned. Simply put, the higher the suction the more effort is required io to push or pull the floor tool over the surface (especially when a carpet or rug with a soft pile) to be cleaned. To date this problem has been addressed by providing a bleed aperture in the wand, so as to reduce the suction clamping effect on the floor tool. Alternatively, a height adjustment mechanism in the support wheels (or brush bar) may be used to stop the base portion from travelling down too far onto the floor or carpet surface. This requires inconvenient height adjustment measures when cleaning different carpet types and can reduce the ability of the drawn-in air to entrain detritus for collection. Too low a setting can cause the floor tool to have reduced mobility on thick pile carpets. Too high a setting can make cleaning ineffective.

The present invention seeks to address these problems and potentially improve cleaning performance in vacuum cleaners equipped with floor tools of the type described in the foregoing.

According to one aspect of the present invention there is provided a floor tool for a vacuum cleaning machine, which floor tool comprises an upper housing having a front region, two opposed side regions, and a rear region, wherein an underside of the tool comprises a floor-facing base portion, the base portion being provided with a transversely extending upwardly recessed channel, wherein the channel is provided with an exit aperture which feeds into a suction conduit for communicating with suction generating means in the vacuum cleaning machine, the arrangement being such that in use fluid is drawn from the tool underside into the recessed channel and m out of the exit aperture into the suction conduit.

The invention may be characterised in that the housing is formed with a plurality of elongate ducts which each extend from an exterior of the housing into the channel, so that in use air is ducted via the housing into the channel so as to form an air jet projecting from each duct.

is Each duct is preferably oriented so as to project air onto the underlying floor surface under the channel. Each duct may have a tapered profile so as to accelerate ducted air into a jet in the channel. In a preferred arrangement each duct has, or includes, a generally conical form. Other duct shapes are possible, such as flat slots, stepped ducts, square section holes, cylinders or the like. Conical ducts have proved to be effective in producing air jets and are thus preferred.

In another aspect of the invention the housing may be provided with a bank of spaced apart elongate ducts distributed along a front region of the housing. The housing may be provided with a bank of spaced apart elongate ducts distributed along a rear region of the housing.

Each duct may oriented obliquely with respect to the floor surface under the channel. This allows the jetted air to dislodge dirt mostly sideways, which is highly effective. Each duct may jet from front and/or rear walls of the channel.

As is common in the art, the floor tool may be provided with support wheels or rollers. These keep the tool at an optimum height over the floor being swept/cleaned and assist in easy travel over a floor. There may be a single wheel disposed in the region of each corner of the base portion. In other embodiments there may be two wheels disposed side by side at the rear region of the tool.

The base portion may comprise a lower wall of a floor tool, or a plate formed as 113 desired.

The suction conduit may typically comprise a tubular member directed to the rear of the tool. The conduit may be adapted to be engaged with a wand portion of a canister-type vacuum cleaner or upright cleaner with wand. Alternatively, the floor tool may be integrated into a work head of an upright vacuum cleaner.

A brush bar for agitating the underlying floor surface may be provided spanning the two opposed sides of the work head. This may act in advance of the recessed channel so that brush-dislodged detritus is drawn into the channel for collection in the vacuum cleaner.

Following is a description by way of example only, and with reference to the figures of the drawings, of modes for putting the present invention into effect.

In the drawings: Figure 1 is a schematic side view, partially in section, of a work head in accordance with an embodiment of the invention.

Figure 2 is a schematic three-quarter perspective view of the front of the work head. Figure 3 is a schematic side view, partially in section, of the work head.

In figure 1 a work head in accordance with the invention is designated generally as 10. There is a housing 11 which has an inclined front face 12 and inclined rear face 13. There is a top surface 14 and front and rear wheels 15, 16. There is an end-on cylindrical swivel member 17 which permits perpendicular cylindrical tubular conduit 18 to swivel (pivot) up and down. The swivel member is formed with a rectangular curved cutout 32 (see figure 2). The cut out communicates with a central portion 33 of the roof of the channel and thus receives air drawn in from the channel 25, which io is then drawn into to the tubular conduit 18, see arrow F in figure 3. The conduit is formed with an elbow joint 19. The free end 20 of the conduit is attached to a distal end of a vacuum cleaner wand (not shown) which provides suction in the direction of arrows S. An underside of the work tool is formed and a flat base portion 21, with a leading portion 22 and a trailing portion 23. Between the leading and trailing portions is there is a recessed transversely extending channel 25. The channel faces downwards, with a semi-circular or U-section shape (or any other selected section shape), which defines front 26 and rear 27 channel walls.

The front region of the work head is formed with a moulded conical tapering duct such as indicated at 28. A corresponding moulded tapering duct 29 is formed in the rear region of the work head. There is a plurality of ducts, the arrangement of which is best shown in figure 2. There are two rows of mutually offset ducts on the front face 12 of the work head. Similarly on the rear face 13. As stated above, the ducts are conical in shape, tapering at their lower ends. For the sake of clarity the conical ducts are not shown throughout the tool, but their configuration and orientation is evident from the ducts 28 and 29 shown on the right hand side of the work tool shown in figure 2. In use, air from above the housing is drawn into the surface holes in faces 12 and 13 (see arrows D and D'). The air (indicated by the fine dots in the ducts 28,29 and channel 25 of fig.1) accelerates due to the narrowing of the ducts, and jets from these ducts in an oblique direction from the front wall 26 of channel 25 and rear wall 27, as shown in figure 1. The jets are angled to impinge upon the floor surface under the mid-region 30 of the channel 25. The mid-region 30 is subject to an over-lap of front and rear jets which agitates the underlying carpet or floor, helping to displace and dirt, debris or detritus from the surface. The ducts also act as bleed valves, reducing the suction acting on the underside of the base portion caused by air entering the channel past the leading and trailing faces 22, 23.

The present invention addresses the problem of reduced mobility of floor tools over carpets and rugs due to suction clamping, whilst providing an improved cleaning action. The work tools in accordance with the invention improve the amount of surface agitation through suction air distribution or redirected suction air into the floor tool air channel. In addition, this also improves the floor tool travel over a given surface to be cleaned by reducing the amount of force required to move the floor tool over the surface whilst under suction. This applies mostly on carpet or rugs, whereas when cleaning hard floors the resistance to travel is naturally reduced. As such the ducts act as bleed valves preventing over-suction on carpets/rugs.

The floor tool design incorporates a number or series of air ducts which can be placed anywhere around or within the floor tool housing or associated structure. These air ducts may be conically shaped which reduce down to a small opening that enters the main air channel. So, air is drawn through a number of conically shaped air ducts which vent into the main air channel within the floor too. The conically shaped air ducts can be set at any angle in relation to the base portion's surface to direct the airflow where required. The air is drawn via suction through the initial larger opening of the conically shaped air ducts. This constraint to the air causes it to increase air flow velocities as the air moves towards the smaller opening at the opposite end of the ducts. The smaller opening jets the air into the main channel.

This increased velocity air flow impacts or agitates a given surface to be cleaned. The increased velocity air flow aids the disturbance and or removal of dust or detritus resting on or in the surface to be cleaned.

With a plurality of air ducts entering the main air channel or suction slot the problem io of excessive suction effect clamping the floor tool base portion to the surface to be cleaned is reduced, thereby alleviating the base portion pressure which subsequently decreases the amount of force or effort required to move the floor tool over a given surface to be cleaned.

The conically shaped air path(s) can be positioned anywhere within the floor tool is structure leading to the main channel. The size, diameters and or depth of the conically shaped air path(s) can be various dimensions to control the amount and speed of air flow entering the main channel within the floor tool. In addition to this controlled air flow, the floor tool base portion may or may not have side venting to the main channel. The floor tool may also additionally incorporate a rotating or oscillating beater bar or brush roller to furthermore agitate the surface to be cleaned.

Claims (15)

1. Claims 1. A floor tool for a vacuum cleaning machine, which floor tool comprises an upper housing having a front region, two opposed side regions, and a rear region, wherein an underside of the tool comprises a floor-facing base portion, the base portion being provided with a transversely extending upwardly recessed channel, wherein the channel is provided with an exit aperture which feeds into a suction conduit for communicating with suction generating means in the vacuum cleaning machine, the arrangement being such that in use fluid is drawn from the tool underside into the recessed channel and out of the exit aperture into the suction conduit, characterised in that the housing is formed with a plurality of elongate ducts which each extend from an exterior of the housing into the channel, so that in use air is ducted via the housing into the channel so as to form an air jet projecting from each duct.
2. 2. A floor tool as claimed in claim 1 wherein each duct is oriented so as to project air onto the underlying floor surface under the channel.
3. 3. A tool as claimed in claim 1 or claim 2 wherein each duct has a tapered profile so as to accelerate ducted air into the channel.
4. 4. A floor tool as claimed in claim 3 wherein each duct comprises a generally conical form.
5. 5. A floor tool as claimed in any of the preceding claims wherein the housing is provided with a bank of spaced apart elongate ducts distributed along a front region of the housing.
6. 6. A floor tool as claimed in any of the preceding claims wherein the housing is provided with a bank of spaced apart elongate ducts distributed along a rear region of the housing.
7. 7. A floor tool as claimed in any of the preceding claims wherein each duct is oriented obliquely with respect to the floor surface under the channel.
8. 8. A floor tool as claimed in claim 7 wherein each duct jets from front and/or rear walls of the channel.
9. 9. A floor tool as claimed in any of the preceding claims and provided with support wheels or rollers.
10. 10. A floor tool as claimed in claim 9 wherein there is a singe wheel disposed in the region of each corner of the base portion.
11. 11. A floor tool as claimed in any of the preceding claims wherein the suction conduit comprises a tubular member directed to the rear of the tool.
12. 12. A floor tool as claimed in any of the preceding claims wherein the tool is adapted to be engaged with a wand portion of a canister-type vacuum cleaner.
13. 13. A floor tool as claimed in any of the preceding claims wherein the tool is integrated into a work head of an upright vacuum cleaner.
14. 14. A floor tool as claimed in any of the preceding claims wherein a brush bar for agitating the underlying floor surface is provided spanning the two opposed sides of the work head and disposed in advance of the recessed channel so that brush-dislodged detritus is drawn into the channel.
15. 15. A floor tool as claimed in claim 14 wherein the brush bar is adapted to be driven so as to rotate or oscillate and thereby agitate the surface to be cleaned.