Patent Description:
Conventional floor cleaners generally comprise a head which engages with the ground surface and through which dust, dirty water and other debris is collected. The head generally contains a device for guiding dust, such as a brush or bladed structure, towards an inlet duct within the head, so that said dust can be drawn into the cleaner by induced airflow. The body of the cleaner contains means for separating and collecting the dirt and dust that is drawn into the cleaner by a motor and fan unit and disposed in the body. In a so-called canister cleaner, the head is pivoted at the end of a tubular wand which is connected to the body of the cleaner by an elongate flexible duct. Sometimes the head may be detachable, so that the user can fit other kinds of cleaning tools to the wand.

<CIT> discloses once such floor cleaning head for moving forwardly and rearwardly along an axis over a floor surface to be cleaned, the head comprising a body portion and a nozzle portion attached to the body portion, the nozzle portion comprising front and rear elongate blades formed of a resiliently flexible material depending from the underside thereof, and a suction mouth disposed on the underside thereof between the blades.

Floor surfaces which are regularly used can often be difficult to clean thoroughly, due to the build up of dust, dirt and other debris attracted through regular use. Steam cleaners are a known way of removing such engrained dirt and dust.

A first type of known steam cleaner simply comprises a steam outlet directed at the floor surface. Disadvantages of this cleaner are that it leaves the floor surface wet, it does not remove dirt and dust, and leaves smears and stains on the floor.

A second type of known steam cleaner comprises a steam outlet directed at the floor surface and a pad or so-called mop which is intended to clean and dry the floor after the steam has been deposited. Disadvantages of this cleaner are that it does not remove dirt and dust, the mop requires frequent cleaning or replacement due to its limited absorptive capacity, and the mop leaves smears and stains on the floor.

A third type of known steam cleaner is similar to the second type but further comprises vacuum cleaner. In use, the floor is firstly cleaned with the vacuum cleaner to pick up dry dirt and dust. The vacuum is then halted and a separate steam cleaning operation is then performed in a similar manner to the second type of known steam cleaner. Whilst this type of cleaner is able to remove dirt and dust, the mop still requires frequent cleaning or replacement due to its limited absorptive capacity, and the mop leaves smears and stains on the floor.

A fourth type of known steam cleaner is able to simultaneously steam and vacuum the floor but it leaves floors damp and is very cumbersome and strenuous to use.

We have now devised an improved floor cleaning head which aims to provide enhanced cleaning of floor surfaces which allows the removal of both dust and larger debris, as well as minimising streaks, stains and any residual water left on or within the ground surface.

In accordance with the present invention there is provided a floor cleaning head of the type disclosed in <CIT>, which is characterised in that the nozzle portion is pivotally attached to the body portion for rotation about a transverse axis (x - x) which extends parallel to the suction mouth, means being provided for pivoting the nozzle portion in a first direction such that the suction mouth faces forwardly and the front blade is raised away from a floor surface when the head is moved forwardly across the surface and for pivoting the nozzle portion in a second direction such that the suction mouth faces rearwardly and the rear blade is raised away from the floor surface when the head is moved rearwardly across the surface.

In use, when the head is moved forwardly the nozzle pivots, such that the rear blade is biased against the floor surface and against which dust and dirty water may be collected as well as raising the front blade to allow dirt and dust to pass unhindered under the suction mouth where it is removed by the induced suction. Steam may be applied to the floor surface through a steam outlet, thereby assisting with the removal of engrained dirt from the floor surface. The rear blade is biased against the floor surface and collects the condensed dirty water formed by the application of the steam as well as any dust particles which were not initially picked up by the suction mouth.

When the head is moved rearwardly the nozzle pivots, such that the front blade becomes biased against the floor surface and such that the rear blade is raised. In this manner, the head operates in reverse to its forward operation.

The present invention thus provides a floor cleaning head that leaves the floor surface perfectly dry in a single pass. The head also leaves the floor surface clean in a single pass without having to perform a separate vacuuming operation.

Preferably, the nozzle portion of the head contains a transversely extending elongate steam outlet disposed on the underside thereof between said blades.

Preferably, the steam outlet divides the suction mouth into front and rear transversely extending portions.

Preferably the nozzle is pivoted about an axis which extends transverse the head at the front thereof, a pair of ground-engaging support wheels preferably being mounted for rotation about said axis at respective opposite ends of the nozzle.

The nozzle may be pivoted in the first and second directions by frictional engagement of a portion of the head with the floor surface. However, it is preferred that the nozzle is pivoted by an actuator mechanism arranged to pivot the nozzle according to the direction of movement. The actuator mechanism may be purely mechanical or it may comprise an electrical actuator such as a motor, a solenoid or electromagnet.

Preferably the mechanism comprises a sensor for sensing the direction of movement of the head. Preferably the sensor outputs an electrical signal to said electrical actuator according to the direction of movement of the head.

Preferably the head comprises a ground engaging wheel, said sensor being arranged to sense the direction of rotation the wheel. Preferably the sensor comprises a clutch which is rotated by the wheel to move a cam between a first and second position according to the direction of rotation of the wheel, said cam acting to open and close a switch according to the direction of rotation of the wheel.

An embodiment of the present invention will now be described by way of an example only and with reference to the accompanying drawings, in which:.

Referring to <FIG> and <FIG> of the drawings, there is shown a floor cleaning head <NUM> in accordance with the present invention for fitting to a steam vacuum cleaner, the rear of the head <NUM> comprising an outlet duct <NUM> for coupling to the suction inlet of the vacuum cleaner (not shown), the outlet duct <NUM> being pivotally mounted to a body portion <NUM> of the head <NUM>. In use, a motor and fan unit in the body of the vacuum cleaner draws a mixture of air, steam, debris and water through the head <NUM>.

The body portion <NUM> comprises a chassis <NUM> having a pair of wheels <NUM> mounted at the rear thereof on an axle <NUM>. An elongate transversely extending nozzle <NUM> which is pivotally mounted to the front of chassis <NUM> for rotation about a transverse axis X - X parallel to the floor surface. The nozzle <NUM> is pivotally supported at its ends on axles <NUM> on which ground-engaging wheels <NUM> are also provided.

The nozzle <NUM> comprises a hollow housing <NUM> having a front portion 19F and a rear portion 19R which define a downwardly-facing elongate suction mouth <NUM> that extends transversely of the head <NUM> on the underside thereof. The nozzle <NUM> is connected to the outlet duct <NUM> via an elongate flexible duct <NUM> which extends from a port <NUM> on the rear portion 19R of the housing <NUM>.

The direction of orientation of the nozzle <NUM> is altered by a mechanism <NUM>, which causes the orientation of the nozzle <NUM> to alter depending upon the direction of motion of the head <NUM>. The mechanism <NUM> is activated by a micro-switch <NUM>, which is actuated by a cam <NUM> that is driven by a simple clutch <NUM> disposed on the axle <NUM>, such that the micro-switch <NUM> is only actuated when the wheels <NUM> turn in the direction of forward movement of the head <NUM>. The micro-switch <NUM> is not actuated when wheels <NUM> turn in the direction of rearward movement of the head <NUM>. The output of the micro switch <NUM> is connected to a motor <NUM> that drives a gearbox <NUM> having an output shaft which is driven clockwise and anticlockwise respectively as the head <NUM> moves forwardly and rearwardly. A rotary wheel <NUM> is mounted on the output shaft of the gearbox <NUM>, the wheel <NUM> comprising a spigot <NUM> which extends axially outwardly from a point which is radially offset from the rotational axis of the wheel <NUM>. An elongate actuator arm <NUM> is rigidly fixed to the rear portion 19R of the nozzle housing <NUM>. The spigot <NUM> engages within an elongate mouth <NUM> which extends longitudinally of the actuator arm <NUM>.

A pair of elongate resiliently flexible wiper blades <NUM>, <NUM> depend from the lower edges of the front and rear walls of the nozzle <NUM> respectively. The blades <NUM>, <NUM> are respectively disposed forwardly and rearwardly of the suction mouth <NUM> and extend the entire length thereof to form seals in front of and behind the suction mouth <NUM>. An elongate channel-section steam bar <NUM> is mounted inside the nozzle housing <NUM> longitudinally of the suction mouth <NUM>, the bar <NUM> dividing the suction mouth <NUM> into front and rear portions 20F, 20R. The channel <NUM> of the bar <NUM> faces downwardly and a steam inlet duct <NUM> extends upwardly from the centre of the bar <NUM>, the lower end of the inlet duct <NUM> being connected to the channel. A steam generator (not shown) mounted in the body of the cleaner delivers steam to the inlet duct <NUM> via a flexible duct (not shown) connected thereto.

Referring to <FIG> of the drawings, in use when the head <NUM> is moved forwardly, the motor <NUM> is controllably driven to bring the spigot <NUM> into its lowermost position: this causes the arm <NUM> to lower, thereby pivoting the nozzle <NUM> in a first direction about the axis X - X into a first position, such that the rear blade <NUM> is compressed slightly against the ground surface and such that the front blade <NUM> is raised to provide a gap of <NUM> and <NUM> between its lower edge and the floor surface: this allows large dust and debris particles to pass underneath the head <NUM>, where they are drawn into the head <NUM> through the front portion 20F of the suction mouth <NUM>.

Steam can be selectively applied to the head <NUM> via the inlet duct <NUM> where it is directed, through the channel <NUM>, onto the floor surface S by the steam bar <NUM>. The steam acts to clean the floor surface S with some of the steam condensing into water. The rear blade <NUM> is deformed rearwardly under compression and creates a highly effective seal with the floor surface S across the trailing edge of the head which acts to substantially collect all water and moisturised dust into a position where it is then drawn into the head <NUM> through the rear portion 20R of the suction mouth <NUM>.

Referring to <FIG> of the drawings, in use when the head <NUM> is moved rearwardly, the motor <NUM> is controllably driven to bring the spigot <NUM> into its uppermost position: this causes the arm <NUM> to raise, thereby pivoting the nozzle <NUM> in a second direction about the axis X - X into a second postion. It will be appreciated that as the nozzle <NUM> pivots from the first to the second positions it passes through a neutral position in which both blades <NUM>, <NUM> are in contact with the floor surface S. The highly effective sealing provided by the front and rear blades <NUM>, <NUM> allow a considerable level of suction to be generated under the nozzle <NUM>, such that any accumulated water, moisture or debris remaining between the blades <NUM>, <NUM> from the previous stroke are quickly drawn into the suction mouth <NUM> as the rear blade <NUM> breaks its seal with the floor surface and suction normalizes.

Once the nozzle <NUM> reaches the second position, the head <NUM> operates in the same manner as the forward direction but with the roles of the blades <NUM>, <NUM> and the front and rear portions 20F, 20R being reversed.

Claim 1:
A floor cleaning head (<NUM>) comprising a body portion (<NUM>) and a nozzle portion (<NUM>) attached to the body portion (<NUM>), the nozzle portion (<NUM>) comprising:
front and rear transversely extending elongate blades (<NUM>,<NUM>) formed of a resiliently flexible material depending from the underside thereof; and
a suction mouth (<NUM>) disposed on the underside thereof between said blades (<NUM>,<NUM>);
characterised in that the nozzle portion (<NUM>) is pivotally attached to the body portion (<NUM>) for rotation about a transverse axis (x - x) which extends parallel to the suction mouth (<NUM>), means being provided for pivoting the nozzle portion (<NUM>) in a first direction such that the suction mouth (<NUM>) faces forwardly and the front blade (<NUM>) is raised away from a floor surface (S) when the head (<NUM>) is moved forwardly across the surface (S) and for pivoting the nozzle portion (<NUM>) in a second direction such that the suction mouth (<NUM>) faces rearwardly and the rear blade (<NUM>) is raised away from the floor surface (S) when the head (<NUM>) is moved rearwardly across the surface (S).