Floor treatment machine

The floor treatment machine addresses brush deformation and maneuvering issues by employing a retractable support mechanism that shifts weight to primary wheels, ensuring easy transport and protection of bristles without tilting the workheads, enhancing usability and efficiency.

EP4262505B1Active Publication Date: 2026-05-20NUMATIC INTERNATIONAL LIMITED
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Patent Information

Authority / Receiving Office
EP · EP
Patent Type
Patents
Current Assignee / Owner
NUMATIC INTERNATIONAL LIMITED
Filing Date
2021-12-15
Publication Date
2026-05-20

AI Technical Summary

Technical Problem

Existing floor treatment machines face issues with brush bristles or pads deformation due to machine weight, and cumbersome maneuvering during storage and transport, often requiring complex mechanical solutions or user intervention to tilt heavy workheads.

Method used

A floor treatment machine design that allows for a retractable support mechanism, enabling the workheads to remain parallel to the floor during use while shifting weight to primary wheels for travel, using a simple actuation mechanism to deploy and retract supports without tilting the workheads.

Benefits of technology

Enables easy maneuverability and protection of bristles during storage and transport, reducing mechanical complexity and user intervention, while maintaining effective scrubbing performance.

✦ Generated by Eureka AI based on patent content.

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Abstract

The present invention concerns the field of floor treatment machines, including floor scrubbers, polishers and sweepers. The invention particularly relates to walk-behind floor scrubbers having one or more rotating workheads. The invention provides a floor treatment machine comprising a base portion provided with one or more rotatably driven floor-engaging treatment workheads and primary wheel means for supporting at least part of the weight of the machine during travel over a floor surface, the machine having a working configuration in which the weight of the machine is shared between the wheel means and the workheads, and wherein a retractable support is provided which is capable of extending downwards with respect to the workheads from a retracted position in which the support is vertically spaced apart from the floor to a deployed position in which the support acts on the floor so that weight previously taken by the workheads is relieved by the support. Each workhead preferably comprises a floor-facing disc which in a working configuration is substantially parallel to the floor, and when the support is deployed so as to act on the floor the floor facing disc is spaced apart from the floor but remains substantially parallel thereto and supported by the primary wheel means and the support. The support may comprise a wheel, roller, skid or knob. An actuation mechanism for the support deployment may be arranged so that rearward tilting of the base portion about the primary wheel means beyond a predetermined tilt angle causes an actuation traveller to travel under the biasing so as to automatically move the support from its retracted position to the deployed position.
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Description

[0001] The present invention concerns the field of floor treatment machines, including floor scrubbers, polishers and sweepers. The invention particularly relates to walk-behind floor scrubbers having rotating workheads.

[0002] Known floor scrubbers typical have a one, two or three disc-shaped workheads each having a vertical axis of rotation and a circular or annular scrubbing surface typically made of bristles, or a polishing pad. Alternatively, the workhead can be cylindrical in configuration and mounted transversely in the machine with brush bristles projecting radially on the outside surface. These workheads are driven by electric motors, via a battery or more usually mains electrical power. Typical scrubbers have a cleaning liquid fluid dispenser by which detergent or dilute cleaning solution can be distributed over the floor surface in advance of, or through, the workhead. A squeegee suction collector is trailed behind the workheads to entrain and collect dirty cleaning liquid from the floor surface for storage in the machine.

[0003] One problem relates to storage of these machines between uses. The brush bristles or pads can become deformed due to the weight of the machine acting on the work heads and associated brushes or polishing pads. Similarly, it may be necessary to move the machines between working locations (such as from one room to another, or between buildings). In this case the drag of the workhead prevents unhindered travel. It is therefore known to provided tilting workheads or workhead decks which may be rotated away from a floor facing orientation to rest on an edge of the workhead such as is shown in GB2274977A (Numatic International Ltd). Rollers or wheels may be provided on the workhead or deck edge to facilitate travel when tilted. Other solutions may be used, such as in the case of large wheeled machines in which the workheads are mechanically retracted from the floor during storage so that the wheels carry the weight of the machine and thus prevent deformation of the bristles during storage. US5765250 discloses another such floor cleaning device with a primary set of wheels and a second set of wheels which can be deployed to reduce the size of the machine when stored and not in use. When the second set of wheels are deployed, the base portion is rotated by 90° so that the workhead is also rotated. Another such machine is shown in US20140144467A1 which discloses a walk-behind floor scrubbing machine comprising a transverse cylindrical cleaning head mounted in a deck which can be lifted-up relative to the machine chassis on a lever arm. However, the workheads with their electric motors are heavy and require expensive lift mechanisms.

[0004] GB2452548 discloses a vacuum cleaner with a cleaning head behind which, is a large roller and a stand. The stand enables the vacuum to be supported in an upright supporting position when the vacuum is not in use and can be moved into an inactive stored position when the vacuum is in use. The movement from the supporting position to the stored position is in response to movement of the main body of the vacuum being tipped rearwardly until its weight is over centre of the stand. A cam arrangement may be present to urge the stand into the supporting position when the main body is moved from an inclined position to an upright position. EP1989983 (Santoemma) discloses a carpet cleaning machine which also includes a brush group 13 mounted on a horizontal axis. DE 11 44 444 B discloses a further floor treatment apparatus with a disc brush.

[0005] The present invention seeks to provide a floor treatment machine which can adopt a storage configuration or travel configuration which does not involve the user having to manipulate or tilt a heavy workhead onto its side, and / or requires less mechanical complication or user intervention.

[0006] In accordance with one aspect of the present invention there is provided a floor treatment machine comprising a base portion provided with one or more rotatably driven floor-engaging treatment workheads and primary wheel means for supporting at least part of the weight of the machine during travel over a floor surface, the machine having a working configuration in which the weight of the machine is shared between the wheel means and the workheads, and wherein a retractable support is provided which is capable of extending downwards with respect to the workheads from a retracted position in which the support is vertically spaced apart from the floor to a deployed position in which the support acts on the floor so that weight previously taken by the workheads is relieved by the support. This can be achieved without having to tilt the workheads out of their working orientation.

[0007] The machine may be configured so that when the support is in the deployed position each workhead is spaced apart from the floor. By deploying a support, the bristles are not loaded during storage and can thus maintain their shape.

[0008] In preferred arrangements each workhead comprises a floor-facing disc which in a working configuration is substantially parallel to the floor, and when the support is deployed the floor facing disc is spaced apart from the floor but remains substantially parallel thereto.

[0009] The machine is preferably configured as a compact floor treatment machine which has a generally upstanding handle portion for directing the machine, the handle portion may be connected to the base portion via an articulation which permits reclining of the handle portion. The articulation preferably comprises a twin axis universal joint arrangement which permits movement of the handle portion to recline up and down, and from side to side, while permitting torque to be applied via the handle portion to the base portion for swivel steering. This makes the machine highly manoeuvrable and easy to steer and swivel around the primary wheel means. One machine of this type is disclosed in WO2019207290A2 (Numatic International). The handle may be lockable in a vertical or substantially vertical position. Such a locking mechanism is shown in WO2019207289A1 (Numatic International).

[0010] The handle portion may be provided with ancillary units, such as a clean water reservoir and a waste waster tank. The waste water tank may be fed by a squeegee suction collector which is towed behind the workhead(s). The squeegee collector will be provided with a conduit to a suction generator for drawing up liquid from the collector.

[0011] The support may comprise one or more wheel or roller or skid or knob. In a preferred arrangement the support comprises a castor wheel assembly, preferably a single wheel, most preferably disposed between and forward of two side-by-side disc-shaped workheads. The workheads may be angled slightly form the vertical and contra-rotate so as to provide forward propulsion, in a manner known in the art.

[0012] The support maybe disposed at a front region of the base portion and the primary wheel means are disposed at a rear region of the base portion. The primary wheel means may comprise two space apart wheels. They may have a common axle (or axis of rotation). The primary wheels are intended to be in contact with the floor during use of the machine and for storage or transit. In some embodiments the primary wheel means may be retracted during use so that the weight of the machine is supported entirely by the workhead or heads. The primary wheel means are typically located in a rear region of the base portion. The support is typically at a front region of the base portion or machine.

[0013] The machine typically includes a generally vertically lockable handle portion, which can be used to lever the machine onto the rear wheels for access to the underside of the base portion for brush replacement or servicing. The machines can be manoeuvred in this tilted transport configuration. However, the support will need to be deployed when the machine is stored, so as to protect the bristle shape. The handle portion may be attached to the base portion of the machine via an articulated joint, preferably a dual axis universal joint arrangement.

[0014] The machine is typically provided with a support actuation mechanism by means of which the support may be deployed by a user. The actuation mechanism may be adapted to shift the primary wheel means down as the support is deployed and shift the primary wheel means up as the support is retracted.

[0015] The support actuation mechanism may comprise a lever or pedal which can be pushed in one direction by a user to deploy the support. The lever or pedal can be pushed in another direction to retract the support. In a preferred arrangement the lever or pedal is depressed to deploy and lifted to retract the support.

[0016] The lever or pedal may act to shunt an elongate strut in an axial direction, the strut being connected to the support so that shunting one way or the other results in deployment or retraction of the support. The strut may extend between an actuation lever at a rear region of the machine and the support means at a front region of the machine.

[0017] The actuation lever may form part of a crank arm which carries the primary wheel means, the crank arm being pivotably mounted on the machine base portion so that pivoting of the crank arm in opposite directions shifts the primary wheel means up or down whilst causing or permitting retraction or deployment of the support.

[0018] The strut may be connected at a rear end region thereof to a lower region of the crank arm. The strut may be connected at a front region thereof to the support so that as the crank arm pivots one way of the other the support is deployed or retracted.

[0019] The strut may be accommodated for axial sliding in a location collar or sleeve. The strut may be connected to the crank arm and / or support via respective axially projecting conrods. The conrods may each be joined to the front or rear ends of the strut by pivot joints. The respective distal ends of each conrod may be attached to the crank arm at one end and to the support at the other end.

[0020] The support may comprise a pivoted lever arm with a support feature such as a skid, knob, wheel or roller at the free end thereof. The support may comprise a lever arm which is pivotally attached to the base portion of the machine, the pivot having a generally transverse orientation so that retraction and deployment of the support is associated with rotation of the arm about the pivot in opposite directions.

[0021] Biasing means may be provided which act to assist deployment of the support, and / or which act to hinder retraction of the support.

[0022] The biasing means may act between the machine base portion (typically a fixed feature such as a bracket) and an actuation traveller, such as the crank arm or primary wheel axle or elongate strut or a conrod.

[0023] In a most preferred aspect of the invention the actuation mechanism is arranged so that rearward tilting of the base portion about the primary wheel means beyond a predetermined tilt angle causes the actuation traveller to travel under the biasing so as to automatically move the support from its retracted position to the deployed position.

[0024] The primary wheel means may be attached to a pivoted crank arm so that the wheels' axis of rotation can rock with the crank arm. The weight of the machine acting on the crank arm and wheel means may provide a weight constraint which keeps the primary wheel means in a rear position.

[0025] The crank arm pivot may be disposed at a height above and forward of a rotation axis of the primary wheel means so that as the base portion is tilted rearwardly the crank arm pivot approaches an oversquare disposition with respect to the axis of rotation. Because of the biasing means it may not be necessary for the crank arm pivot to actually reach the oversquare disposition, as the biasing means will overcome the any remaining weight constraint.

[0026] So, the biasing means may act on the crank arm or wheel rotation axis to counteract the weight constraint, so as to facilitate forward rocking of the crank arm and wheel means away from their constrained rear position.

[0027] The crank arm or an axle of the primary wheel means may be connected to an elongate strut in the actuation mechanism, the arrangement being such that rocking of the crank arm or axle shunts the elongate strut forwardly so as to deploy the support. Any of these arm, axle or strut may serve as a traveller component. The extent of travel of the elongate strut or crank arm or axle may be limited by a pin and slot arrangement. The slot may be arcuate in form. The slot is preferably provided with an intermediate neck region between front and rear ends thereof which neck region resists free travel of the pin relative to the slot absent the application of a threshold bypass force. In a preferred arrangement the slot is generally kidney shaped.

[0028] The support may comprise an arm which is pivotally attached to the base portion of the machine, the pivot having a generally transverse orientation so that retraction and deployment of the support is associated with rotation (rocking) of the arm about the pivot in opposite rotational directions.

[0029] The actuation mechanism may be arranged so that rearward tilting of the base portion on the primary wheel means causes a traveller component to travel under the biasing so as to move the support from its retracted position to the deployed position.

[0030] The biasing means may operate between the machine base portion and an actuation mechanism component, which may be the traveller component. The biasing means may act on a crank which carries the primary wheel or wheels, which crank is mechanically connected to the elongate strut and any associated conrods. The biasing means may comprise one or more springs, preferably coil springs, most preferably acting in tension.

[0031] The floor treatment machine as hereinbefore described may be configured as a walk-behind floor scrubber. The machine may be configured as a wet floor scrubber, having clean and dirty liquid reservoirs and wherein a squeegee collector is provided which feeds into the dirty liquid reservoir and is disposed behind the base portion with respect to a forward direction of travel. The reservoirs may be carried by the machine handle, the handle being reclinable and lockable substantially vertically when not in use. Electric drive motors may be included in the base portion.

[0032] The squeegee collector may be is provided with a tilt mechanism and latch, which latch is activated automatically when the squeegee is tilted up from the floor by more than a predetermined amount. This allows unhindered transport between work tasks, and storage of the machine without the squeegee blades being deformed under the weight of the collector.

[0033] Following is a description by way of example only of one mode for putting the various aspects of the invention into effect, with reference to the figures of the drawings in which: Figure 1 is a side view of a floor scrubber / drier machine in accordance with the invention. Figure 2 is a side view of the base portion of the same machine with a rotary brush head removed. Figure 3 is a front-end view of the base portion of the machine. Figure 4 is a perspective rear three quarter view of internal components of an actuation mechanism of the present invention. Figure 5 is a schematic side view showing the support actuation mechanism provided in a base portion of the floor scrubber. Figures 6A to 6C show the base portion as shown in figure 5 but with a support wheel sequenced between retracted, half deployed and fully deployed respective positions. Figure 7 is a perspective rear three quarter view of internal components of an actuation mechanism having an alternative arrangement. Figures 8A to 8C are schematic side views of the alternative actuation mechanism. Figures 9A to 9B are side views of the floor scrubbing machine of the present invention showing different operating, transport or storage modes.

[0034] In figure 1 a floor scrubber / drier is shown generally as 10. The machine has an upright handle portion 11 and a base portion 12. Attached to the upright handle portion is an upper housing 13 which includes a clean water reservoir and a dirty water collection tank (neither visible). An upper end region 15 of the upright handle portion is provided with a T-bar which includes left- and right-hand grips (one visible as 14).

[0035] The machine's base region 12 includes a motor housing 16 which includes a two drive motors for two respective disc-shaped work heads (one visible in figure 1 and item 17). A pair of primary support wheels (one visible as 18) are provided at a rear end region of the base portion. A squeegee suction collector assembly 19 is attached to the rear end region of the base portion. The collector assembly is shown in a raised, tilted configuration. The collector assembly comprises a squeegee blade 20 and a hose (not shown) that would feed into the dirty water collection tank. A support wheel 21 for the collector comes into operation when the squeegee assembly is brought down onto a floor surface.

[0036] The base portion 12 is shown in more detail in figure 2. The work head 17 and associated brush unit have been removed from hub 22 in order to show the position and configuration of the front support wheel 23. The support wheel is mounted at a lower end of an arm 24. The upper end 25 of the arm is pivotally attached to the base portion and has a castor mount which permits swivelling of the support wheel 23 when deployed as shown in figure 2.

[0037] In figure 3 a front view of the base portion of the machine is shown. The side-by-side arrangement of the primary support wheels 18 is shown with an axle tube 26 connecting the wheels together. A castor wheel assembly is made up of the two wheel arms 24 and the wheel 23 which is has a transverse rotation axis between the arms. The castor is a fixed castor, in that it does not swivel. However in alternative arrangements a swivelling castor could be provided. There are two side by side motor housings 16 which are carried by a generally planar deck.

[0038] In figure 4 the support wheel actuation mechanism assembly is visible generally as 30. There is a crank arm 31 with a pivot 32 at its elbow. An upper end of the crank arm is provided with a textured rod 33 which serves as a foot pedal. A lower end of the crank arm is attached to the wheel axle tube 26. A central portion of the axle tube carries a lever 34. A rear conrod 25 is pivotably attached to the upper distal end 35 of the lever 34. The axle tube accommodates internally an axle for the two primary support wheels 18. The conrod 25 is attached to a rear end region of a central fore-aft strut (or rod) 26. A front region of the strut is attached to a front conrod 37 via a pivot 38. The conrod is angled downwards towards the upper end of the support wheel arm 24. The front end of the conrod is attached to the wheel arm via a pivoting connection 39.

[0039] In figure 5 the support wheel 23 is shown in its deployed configuration with the parallel arms 24 depending downwards. Schematic side-on views of the actuation assembly are shown in figures 5A to 5C. The strut 26 is slidably accommodated in a cylindrical guide sleeve 40, which permits shifting of the strut forwards and backwards. When the pedal 33 is depressed in the direction of the arrow A shown in figure 6B, the wheel 18 and lower portion 41 of the crank arm are shifted to the right (i.e. to the front of the machine). This displaces the axle 26 and lever 34 to the right, along with conrod 25. Conrod 25 shifts the strut 26 to the right in its sleeve. This shifts the front conrod 37 to the right which causes the support wheel arm 28 to pivot down and partially deploy the support wheel 23, as shown in figure 6B. Continued depression of the pedal arm 33 moves the arm 24 and wheel 23 to their fully deployed positions as shown in figure 5C (and figure 4).

[0040] A variant of the actuation mechanism is shown in figure 7 and figures 8A to 8C. Like features are given like numbers. A pair of parallel biasing springs 45, 46 extend between the axle tube 28 of the rear wheels 18 and forward to a fixed supporting bracket 47, which is attached to a deck plate (not shown). Thus the axle tube is biased forwards. The upper and lower crank arms 31,41 rock around the crank pivot 32, with the axle tube connected to the lower arm 41. So the crank is also biased by the springs, with the lower arm 41 biased forwards and the upper arm 31 correspondingly biased backwards. The upwardly oriented arm 34 is fixed at its lower end to the axle tub 28, so movement of the axle tube forwards under biasing causes the strut and conrod assembly 25, 26, 37 to move forwards. In the absence of external constraint, the biasing acts to urge the primary wheels 18 forwards and down, and the front support wheel 23 forwards and down, as shown in figure 8C.

[0041] Forward motion of the wheels is limited by fixed cheek plate 49 (see figure 8C). The cheeks plate has a kidney-shaped cut-out slot 48 which accommodates a pin 50. The pin is attached at an inner end thereof to the lower crank arm 41. The pin is provided with a nylon cylindrical sleeve having a diameter which permits forward sliding travel of the pin in the slot, but which is pinched by the central upper neck region 36 of the slot. Thus the travel of the pin in the cheek plate forward (and backward) is limited by the opposite ends of the slot. The neck region provides a resistance against free rear movement in the slot so as to prevent sudden collapse (retraction) of the front wheel should the front wheel encounter commonly seen obstacles, such as a ramp or floor crack. The slot also limits backward movement of the biased axle 28. The limit of forward travel of the pin in the slot corresponds to the support wheel assembly 23,24 being in the deployed position, as shown in figure 7 and figure 8C. Thus the support wheel assembly 23,24, and the primary wheels 18 are effectively biased in their deployed positions by the action of the coil springs 45,46.

[0042] The usual working support-retracted position is shown in figure 8A. The position is attained by shifting the foot pedal 33 and upper crank arm 31 forwards so that the pin travels back in the slot 48 as the lower crank arm 41 retreats. The support wheel is held retracted with the pin 50 at the back edge of the cheek plate 49. The pin is retained in the back region of the slot 48 by the neck region 36. The retracted front support wheel is thus spaced apart from the floor surface. The workheads are, in this position, sit on the floor and take the weight of the motor units in housing 16 so as to provide a good scrubbing force. When the cleaning session has finished, and it is desired to wheel the machine to a new location, the handle of the machine may be moved from the reclining position shown in figure 9A to a locked vertical position (by means of an appropriate latch, not shown) with respect to the base portion, so that the base portion and handle positions are at right angles with respect to one another, as shown in figure 9B. The handle may be moved back in the direction of the arrow B in figure 9B to displace the squeegee assembly from a position where it floats on the floor (figure 9A) to a position in which it is inclined upwards (per figure 9C). The squeegee lift mechanism is not described herein and is not essential to the present invention. However, it involves the use of a dedicated latch to catch the rising squeegee assembly in the tilted position, typically at about 40 degrees tilt back. (A second crank arm 51 may be used to un-latch the squeegee assembly).

[0043] In tilting the machine backwards in the direction of arrow B in figure 9B, the front wheel assembly is lifted off the floor as the base portion lifts up. As the tilt increases the crank arm pivot 31 (see figure 8A) rocks backwards about the axle of wheel 18. As the pivot 32 approaches an oversquare relationship with respect to the wheel axle, the machine weight constraint keeping the pin 50 in its rear slot seat becomes reduced, thereby allowing the axle and crank arm 41 to rock forwards under the pivot 32 so that the wheel 18 shifts forwards (and downwards) from position (a) to (b), (as shown in figures 8A and 8B) assisted by the spring biasing. The pin 50 thus moves forward past the neck region 36. Further forward movement causes the rear wheels to arrive at position (c) in figure 8C, with the pin set at the front of the slot 48. This biased movement of the rear wheels in turn shifts the strut 26 correspondingly forwards, along with the front conrod 37 which acts on the lever arm 24 of the wheel assembly and causes the wheel to deploy downwards and forwards in the direction of arrow W. This shifting of the rear wheels 18 and concurrent deployment of the front support wheel occurs automatically on tilting of the base portion away from the floor on the primary support wheels 18. Nevertheless, the same effect (support wheel deployment) can be achieved by a foot pressing down on the foot bat / pedal 33 so as to cause the crank arm to rock about its pivot axis 32, in manner described above in relation to figures 6A to 6B.

[0044] Thus the support wheel is actuated by a simple, user friendly, rearwards tilting of the handle (after locking vertically), which is the natural action an operator would use to facilitate wheeled transport on the rear wheels 18. To retract the support wheel the pedal bar 33 on crank 31 is moved up, and this shifts the sliding strut backwards so that the pin 50 returns to the wheel-retracted position, in which case the pin is set at the back of the slot 48.

[0045] In figure 9A a cleaning mode is shown in which the handle portion is reclined and the squeegee assembly lies on the floor surface. The support wheel is retracted and the workheads are in working contact with the floor surface. In figure 9B a transport mode is shown. The handle portion 11 is locked vertical (perpendicular) with respect to the base portion. The squeegee assembly 20 is in its resting configuration, tilted upwards away from the floor behind the machines. The primary wheels support the machine for transport, with the user steering the machine using the handle portion. The handle portion 11 has been tilted back so that the workheads are lifted from the floor surface.

[0046] The user can deploy the front support wheel by pushing / pressing the pedal 33 downward, but in the alternative preferred embodiment the support wheel is deployed automatically by tilting of the handle in the direction of arrow B. As the weight of the machine shifts to the user holding the handle portion, the weight constraint which keeps rear wheels hard to the rear (as shown in figure 8A) is released enough to permit the rear axle 28 and wheels 18 to shift forwards as the associated crank rocks about pivot 32 under the strong bias of the coil springs 45,46. So the rear axle and associated primary support wheels can shift forwards and downwards, thereby shifting the actuation strut 26 and front support wheel, (as described above for figure 8B). In figure 9C the storage mode is shown, in which the machine has been tilted back down onto the floor with the workheads now lifted off the floor by the deployed support wheel. When next wheeled to a location to be cleaned, the actuation crank 32 and pedal 33 can be lifted (up and forwards) to cause retraction of the wheel so that the machine can be used for scrubbing, with the weight taken by the workheads.

[0047] In summary, the present invention concerns the field of floor treatment machines, including floor scrubbers, polishers and sweepers. The invention particularly relates to walk-behind floor scrubbers having one or more rotating workheads. The invention provides a floor treatment machine comprising a base portion provided with one or more rotatably driven floor-engaging treatment workheads and primary wheel means for supporting at least part of the weight of the machine during travel over a floor surface, the machine having a working configuration in which the weight of the machine is shared between the wheel means and the workheads, and wherein a retractable support is provided which is capable of extending downwards with respect to the workheads from a retracted position in which the support is vertically spaced apart from the floor to a deployed position in which the support acts on the floor so that weight previously taken by the workheads is relieved by the support. Each workhead preferably comprises a floor-facing disc which in a working configuration is substantially parallel to the floor, and when the support is deployed so as to act on the floor the floor facing disc is spaced apart from the floor but remains substantially parallel thereto and supported by the primary wheel means and the support. The support may comprise a wheel, roller, skid or knob, preferably a castor wheel. An actuation mechanism for the support deployment may be arranged so that rearward tilting of the base portion about the primary wheel means beyond a predetermined tilt angle causes an actuation traveller to travel under the biasing so as to automatically move the support from its retracted position to the deployed position.

Claims

1. A floor treatment machine (10) comprising a base portion (12) provided with one or more rotatably driven floor-engaging treatment workheads (17) and primary wheel means (18) for supporting at least part of the weight of the machine during travel over a floor surface, the machine (10) having a working configuration in which the weight of the machine (10) is shared between the wheel means (18) and the workheads (17), wherein each workhead (17) comprises a floor-facing disc substantially parallel to the floor, and characterised in that the machine (10) comprises a retractable support (23), which retractable support (23) is capable of extending downwards with respect to the workheads (17) from a retracted position in which the support (23) is vertically spaced apart from the floor to a deployed position in which the support (23) acts on the floor so that weight previously taken by the workheads (17) is relieved by the support (23) and wherein in the deployed position each workhead (17) is spaced apart from the floor but remains substantially parallel thereto and supported in a spaced position from the floor by the primary wheel means (18) and the support (23).

2. A floor treatment machine (10) as claimed in claim 1, further comprising a generally upstanding handle portion (11) for directing the machine, the handle portion (11) being connected to the base portion (12) via an articulation which comprises a twin axis universal joint arrangement which permits movement of the handle portion (11) to recline up and down, and from side to side, while permitting torque to be applied via the handle portion (11) to the base portion (12) for swivel steering, and wherein the handle portion (11) carries a reservoir for clean water and a waste water tank and wherein the waste water tank is fed by a squeegee suction collector (19) which is disposed for towing behind the workhead(s).

3. A floor treatment machine (10) as claimed in any preceding claim, wherein the support (23) comprises a one or more of a wheel, roller, skid or knob, but preferably a castor wheel assembly.

4. A floor treatment machine (10) as claimed in any preceding claim, comprising a generally upstanding handle portion (11) located at a rear region of the floor treatment machine, wherein the support (23) is disposed at a front region of the base portion distal from the rear region, and the primary wheel means (18) are disposed at a rear region of the base portion (12).

5. A floor treatment machine (10) as claimed in any of the preceding claims, and provided with a support actuation mechanism by means of which the support can be deployed by moving the support (23) from the retracted position downwards to the deployed position. and,wherein the actuation mechanism is adapted to shift the primary wheel means (18) down as the support is deployed and shift the primary wheel means (18) up as the support (23) is retracted.

6. A floor treatment machine (10) as claimed in claim 5, wherein the support actuation mechanism comprises a lever or pedal (33) which can be pressed in one direction by a user to deploy the support (23)and, wherein the lever or pedal (33) can be pushed in another direction to retract the support (23).

7. A floor treatment machine (10) as claimed in claim 6, wherein the lever or pedal (33) acts to shunt an elongate strut (26) in an axial direction, the strut (26) being connected to the support (23) so that shunting one way or the other results in deployment or retraction of the support (23) and wherein the strut (26) extends between an actuation lever (33) at a rear region of the machine (10) and the support (23) at a front region of the machine (10).

8. A floor treatment machine (10) as claimed in claim 6 or claim 7, wherein the actuation lever (33) forms part of a crank arm (31) which carries the primary wheel means (18), the crank arm (31) being pivotably mounted on the machine (10) so that pivoting of the crank arm (31) in opposite directions shifts the primary wheel means (18) up or down whilst causing or permitting retraction or deployment of the support (23).

9. A floor treatment machine (10) as claimed in claim 8, wherein the strut (26) is connected at a rear end region thereof to a lower region of the crank arm (31), and connected at a front region thereof to the support (23) so that as the crank arm (31) pivots the support (23) is deployed or retracted and wherein the strut (26) is connected to the crank arm (31) and / or support (23) via respective axially projecting conrods (25, 37).

10. A floor treatment machine (10) as claimed in any of the preceding claims, wherein biasing means are provided which act to assist deployment of the support (23) and, wherein the biasing means act between the machine base portion (12) and an actuation traveller.

11. A floor treatment machine (10) as claimed in claim 10, wherein the actuation mechanism is arranged so that rearward tilting of the base portion (12) about the primary wheel means (18) beyond a predetermined tilt angle causes the actuation traveller to travel under the biasing so as to automatically move the support (23) from its retracted position to the deployed position.

12. A floor treatment machine as claimed in any preceding claim , wherein the primary wheel means (18) are attached to a pivoted crank arm (31) so that the wheels' axis of rotation can rock with the crank arm (31), and wherein the weight of the machine (10) acting on the crank arm (31) and wheel means (18) provides a weight constraint which keeps the primary wheel means (18) in a rear position.

13. A floor treatment machine (10) as claimed in claim 14,, wherein the crank arm pivot (32) is disposed at a height above and forward of a rotation axis of the primary wheel means (18) so that as the base portion (12) is tilted rearwardly the crank arm pivot (32) approaches an oversquare disposition with respect to the said primary wheel rotation axis, and wherein the biasing means acts on the crank arm (31) or wheel rotation axis to counteract the weight constraint, so as to facilitate forward rocking of the crank arm and wheel means away from their constrained rear position.

14. A floor treatment machine (10) as claimed in any of claims 9 to 13, wherein the crank arm (31) or an axle of the primary wheel means (18) is connected to an elongate strut in the actuation mechanism, the arrangement being such that rocking of the crank arm or axle shunts the elongate strut forwardly so as to deploy the support (23), and, wherein the extent of travel of the elongate strut or crank arm or axle is limited by a pin and slot arrangement and, wherein the slot (48) is provided with an intermediate neck region between ends thereof, which neck region resists free travel of the pin (50) through the slot (48) absent the application of a threshold bypass force on the pin (50) and, wherein the slot (48) is generally kidney shaped.

15. A floor treatment machine (10) as claimed in any of the preceding claims, wherein the support (23) comprises an arm which is pivotally attached to the base portion of the machine (10), the pivot having a generally transverse orientation so that retraction and deployment of the support (23) is associated with rotation of the arm about the pivot in opposite rotational directions.

16. A floor treatment machine (10) as claimed in any of the preceding claims, which is configured as a walk-behind wet floor scrubber / drier, comprising a clean water reservoir and a waste water tank, wherein a squeegee collector (19) is provided which feeds into the waste tank and is disposed behind the base portion (12) with respect to a forward direction of travel, and, wherein the squeegee collector (19) is provided with a tilt mechanism and latch, which latch is activated automatically when the squeegee is tilted up from the floor by more than a predetermined amount.