FLOOR TREATMENT MACHINE

Description

The present invention relates to the field of scrubber-drier floor cleaning or treatment machines, and especially hand-guided, walk-behind machines.

These machines typically have a floor scrubbing portion such as one or more generally disc shaped work heads which are rotatably driven on a floor surface. An under surface of the work head is provided with brush elements for agitating the floor. A cleaning liquid is fed onto the floor from a reservoir on the machine. The liquid feed is adapted to deliver the liquid just in front of the work heads so as to permit cleaning of the floor by dislodging dirt or detritus from the floor surface. The dirt/detritus becomes entrained in the liquid, and the liquid is then collected using a liquid suction device, such as a squeegee collector in fluid communication with a suction device and a tank for collection of the dirty water. The squeegee is typically towed behind the work heads as the machine is moved in a cleaning/scrubbing direction. The squeegee collector is elongate and disposed transversely, with leading and trailing lips made or elastomeric sheet material and a roof portion. The lips are generally curved and concave in form with the trailing lip having a smaller curve radius than the leading lip, with outer end regions of each lip abutting each other so as to define an internal suction chamber which is maintained at reduced pressure by the suction device.

A problem with these machines can arise at building features such as doors or corridors where the travel path may narrow causing a risk that the squeegee outer end regions will unintentionally hit a door frame or item of furniture or some other obstruction. This can damage the squeegee collector, or cause it to become detached, or bend it out of shape which permits collected liquid to escape, or resulting in a loss of suction. It may also damage the interior of the building; marking paintwork on door frames or denting furniture. In order to mitigate these impacts the squeegee collector may be provided with a wheel or roller at each opposite outer end region thereof, each wheel or roller having a vertical axis of rotation. This helps prevent the squeegee collector from snagging on the obstruction or leaving damage or marks on the obstruction. There does however remain a chance that the collector may be damaged or deformed when meeting an obstruction and the present invention seeks further to protect to the squeegee collector.

In accordance with one aspect of the present invention there is provided a scrubber-drier machine comprising a base portion provided with one or more floor-facing work heads for scrubbing a floor surface along a working direction, a squeegee collector disposed on the floor so as to trail behind the work head(s), the squeegee collector being in fluid communication with a suction device, and a collection tank for liquid drawn from the suction collector by the suction device. The squeegee collector typically has a transverse orientation and length sufficient to provide a collection path which spans the cleaning path provided by the work heads. The machine may be characterised in that the squeegee connector is attached to the base portion by a mounting which permits limited transverse displacement (i.e. travel) of the squeegee connector either left or right away from a central home position.

In this way, when the squeegee collector touches or hits an obstruction it has freedom to deflect left or right so as to prevent snagging or damage of itself or the obstruction (such as a doorway frame, door, or item of furniture or storage units.

The squeegee collector mounting is preferably provided with resilient biasing means which acts to limit the displacement and return the squeegee connector towards the home position after displacement. In this way the squeegee collector is automatically reset into the home (or desired operating) position after an obstruction is contacted.

The resilient biasing means may comprise one biasing element which limits displacement left and another biasing element which limits displacement right. Left and right means directions transverse to the working direction of travel of the machine during use. Each biasing element may comprise at least one compression spring. Tension springs could of course be implemented to pull the collector back into position. The springs may be leaf springs or coil springs. They may be made of any heavy duty resilient material such as engineering plastics, composites or steel.

In a preferred arrangement the mounting comprises a transverse rod which is slidably received in a correspond in bore in a traveler member. In this way the traveler member may be displaced transversely left or right along the rod whilst remaining the connection with the base portion. The traveler member may comprise a sleeve portion in which is carried the rod. There is preferably also a connection portion which is connected to an upper region of the squeegee collector, typically the roof of the squeegee collector.

The connection between the connection portion and the upper region of the squeegee collector may be made by a failsafe connector which allows the squeegee connector to become detached in the event of a threshold detachment force being reached. This will typically be a rearward force caused by snagging.

The rod and traveler member may serve as a transverse pivot for permitting up/down tilting (pivoting) of the squeegee collector, with the rod acting as an axle for pivoting of the traveler member.

Outer opposite end regions of the rod may be fixed to two side-by-side trailing arms extending from the rear of the machine base portion. Base portion ends of the trailing arms are pivotally attached to the base portion of the machine along a transverse pivot parallel to the rod, so that the squeegee collector can be pivoted up from the floor and set down on floor with the trailing arms.

The dual transverse pivot arrangement allows the squeegee collector to float up and down in response to floor ramps or depressions, whilst maintaining intimate contact of the collector on the floor.

The biasing elements may be disposed on opposite end regions of the rod, with the sleeve portion of the traveler member disposed (preferably centred) therebetween. Transverse displacement of the sleeve portion causes one or other of the biasing elements to resist, with outer constraint allowing elastic deformation of the biasing elements. The distal portions of the trailing arms may conveniently serve as outer constraints against displacement of the biasing elements.

The biasing elements preferably comprise respective compression springs which are each coiled around opposite ends of the rod.

As is known in the art, the squeegee collector may have a generally arcuate form comprising front and rear resilient strips (i.e. squeegee blades) and a roof portion. The roof portion will have a suction port in fluid communication with a suction turbine (typically via a flexible hose). When placed on a flat floor a suction chamber is created, which permits air and waste liquid to be drawn into the chamber. The front strip is typically provided with a plurality of laterally spaced apart apertures which admit air and liquid into the collector chamber. The collector may be supported by floor-engaging wheels or castors so as to prevent downward deformation of the squeegee blades, whilst maintaining an adequate seal for water gathering.

In another aspect of the invention, opposite outer end regions of the squeegee collector are provided with wheels or rollers. Each wheel or roller has a generally vertical axis of rotation so that the wheels serve as rotatable bumpers in the event that the outer end regions impact an obstruction which tends to displace the squeegee collection transversely. The presence of such rotatable bumpers eases the transfer of an rearward impact force to induce transverse travel of the squeegee collector.

The machine is preferably configured as a walk-behind hand guided machine, whereby the machine further comprises a generally elongate handle portion which has a connection at a lower end region thereof which permits the handle portion to pivot with respect to the base portion, and wherein the handle portion has an upper end region which has a grip for guiding the machine in use. The pivot may be a dual axis pivoting arrangement which permits up/down and left/right pivoting of the handle portion, such as by mand of a universal joint which allows torque transfer to the base portion for machine steering.

A cleaning liquid delivery system is preferably provided in the machine which serves to deliver a cleaning liquid from a reservoir to a floor surface in advance of, or under, the work head(s). This may be a simple gravity drip pipe fed by the cleaning liquid reservoir, or a pumped delivery system, with sprayer.

Following is a description by way of example only and with reference to the figures of the drawings of one mode for putting the present invention into effect. In the drawings:

FIG. 1 is a side view of a hand-guided, walk behind scrubber drier in accordance with the present invention.

FIGS. 2A and 2B are top plan views of the base portion and squeegee collector of the machine.

FIG. 3 is a three quarter perspective view of the squeegee collector.

FIG. 4 is a three quarter perspective view of trailing arms and mounting for the squeegee collector.

FIG. 5 is a bottom plan view of the mounting trailing arms and mounting.

FIGS. 6A, 6B and 6C are each bottom plan views of the trailing arms and mountings showing transverse displacement positions either side of a home position.

FIGS. 7A, 7B and 7C are each bottom plan views of the machine showing the squeegee collector in the same transverse displacement positions.

In FIG. 1 a scrubber drier machine in accordance with the invention is shown generally as 10. There is a handle portion 11 which is shown reclined somewhat with respect to the floor 20. An upper region of the handle has a cross bar grip 12 for a user-operator. A mid region of the handle portion is provided with a housing 13 which includes a cleaning liquid reservoir and waste water collection tank (reservoir and tank not visible individually). A suction hose 14 is attached to a port 15 of a squeegee collector 21 which is best seen in FIG. 3.

A base portion 30 of the machine is equipped with a work head 31 comprising a disc-shaped plate provided with an annular array of floor-facing bristles 33. The work head is adapted to be rotated by an electric motor (and transmission) disposed in the base portion housing 32. A cleaning liquid delivery pipe 18 feeds from the reservoir in housing 13 to the scrubbing brush of the work head 31 (within the base portion housing 32). In this embodiment there are two work heads arranged side by side, as shown in FIG. 7B. There are laterally spaced-apart support wheels 34 at a rear end region of the base portion. These wheels are carried at either end of a transverse axle 35. Two parallel side by side trailing arms 36 extend rearwardly behind the base portion and are attached to a squeegee collector mounting assembly 37. The mounting assembly is attached to two transversely spaced apart bosses 38 which are upstanding on a roof portion 39 of the squeegee collector. The attachment is made via two corresponding boss clips 40, which have rearward facing mouths.

The squeegee collector is shown in more detail in FIG. 3. The collector has a transverse synthetic rubber squeegee front blade 42. The blade has a concave arcuate shape and is oriented to be upstanding on the floor 20. A similar rear blade 45 (visible in FIG. 7) is disposed behind the front blade with outer end regions of the blades meeting at opposite ends 43 of the collector. The plan profile of the collector is defined by the roof 39 of the collector. The space between the arcuate front and rear blades 42,45 defines a suction chamber 44 (FIG. 7), which vents via the suction port 15 provided on the roof portion. A central, rear region of the collectors is provided with a support wheel 46. Two further support wheels 47 are provided on forward facing pylons at outer edge regions of the collector. The wheels 46,47 stably support the squeegee collector during use and prevent the rubber blades collapsing when under suction and weight loading during use. Opposite outer extremities of the collector are provided with disc shaped rollers 48. These have a vertical axis of rotation and serve as rolling bumpers for the collector.

In FIGS. 4 and 5 the collector mounting assembly is shown in more detail. The two trailing arms 36 are transversely spaced apart and each have a base portion end 50 formed with a bore for a pivot axis A. The bores receive respective co-axial spigots (not shown) which permit pivoting of the arms up and down. Distal ends 54 of the trailing arms are formed with further bores which receive opposite ends of a transverse rod 51. Opposite outer regions of the rod carry respective coiled compression springs 52, 53. The outer ends of the rod have threaded bores for locking nuts 56.

The mounting 37 has a central sleeve 57 which receives a central portion of the transverse rod 51. The sleeve has outer faces which abut the inner ends of the two coiled springs 52,53. The outer ends of the springs abut the trailing arm distal end regions. The coiled springs act to keep the mounting assembly central on the rod. The sleeve is a sliding fit for the rod, so that the rod provides a pivot axis B about which the mounting assembly can pivot (with the squeegee collector 21 when attached).

In FIG. 6A the mounting assembly is shown displaced to the right with the spring 52 fully compressed, and the opposite spring lazy. FIG. 6B shows the neutral, home position with the mounting central. FIG. 6C shows the mounting assembly displaced to the left, with spring 53 accordingly fully compressed. In each displaced example the compressed spring biases the mounting assembly to return to the centre once any displacement force has been released.

In FIGS. 7A to 7C the mounting assembly is shown with the squeegee collector attached to the clips 40. The squeegee can thus be displaced resiliently left or right. This may be due to the out ends (rollers 48) hitting an obstruction during use. The rollers served to help prevent snagging and translate an impact force into a lateral displacement against the appropriate coiled spring.

The clips 40 are open to the rear and thus provide a failsafe release of the squeegee collector unit from the mounting assembly, in the event that a threshold rearward force is applied to the collector during use. The collector can them be re-attached simply by clipping back the collector onto the bosses 38.

The collector is thus protected against damage by impact with external objects, and is less likely to cause cosmetic or structural damage to the objects such as skirting boards, door frames or furniture etc.