FLOOR TREATMENT MACHINE

Abstract

The present invention concerns the field of floor treatment machines such as scrubbers, finishers or polishers. Floor scrubbers typically have rotating work heads equipped with bristles for working the floor to remove dirt. The invention provides a hand-guided floor treatment machine comprising a handle portion connected to a base portion, which base portion is provided with a rotatable generally disc-shaped floor-facing work head having a substantially vertical axis of rotation, the machine being provided with drive means for rotatably driving the work head, wherein the rotational axis of the work head is slightly tilted away from the vertical in a direction which has a transverse component and a rearward component so that the work head is biased into contact with the floor in a region rearwardly and to one side of the work head, whereby in use rotation of the work head through the biased region provides propulsion predominantly in a forward direction.

Claims

1. A hand-guided floor treatment machine comprising a handle portion connected to a base portion, which base portion is provided with a rotatable generally disc-shaped floor-facing work head having a substantially vertical axis of rotation, the machine being provided with drive means for rotatably driving the work head, wherein the rotational axis of the work head is slightly tilted away from the vertical in a direction which has a transverse component so that a work head side region is biased into enhanced contact with the floor so as to provide machine propulsion predominantly in a forward working direction.

2. A machine as claimed in claim 1 wherein the tilt has a rearward component so that the work head is biased into contact with the floor in a region rearwardly and to the side region of the work head, whereby in use rotation of the work head through the biased region provides propulsion predominantly in a forward direction, along with enhanced contact of the rearward region.

3. A machine as claimed in claim 1 wherein the work head is carried underneath a deck portion of the base portion.

4. A machine as claimed in claim 3 wherein the deck portion supports one or more drive motor.

5. A machine as claimed in claim 1 wherein an output rotor of the motor feeds into an associated transmission unit.

6. A machine as claimed in claim 5 wherein an output shaft of the transmission unit carries a work head hub.

7. A machine as claimed in claim 1 wherein an output rotor of the motor is directly attached to the work head hub, optionally via a drive shaft, and without an intervening transmission unit.

8. A machine as claimed in claim 7 wherein the work head tilt is achieved by tilting away from the vertical of the motor output rotor with hub, and/or the transmission unit output shaft with hub.

9. A machine as claimed in claim 8 wherein tilting of the output shaft is achieved by fixing a transmission unit in a tilted disposition with respect to the deck portion upon which the transmission unit is mounted.

10. A machine as claimed in claim 9 wherein the transmission unit is tilted by means of one or more spacer elements disposed between the transmission unit and the deck portion.

11. A machine as claimed in claim 8 wherein the motor output rotor is tilted away from the vertical by means of one or more spacer elements disposed between a mounting for the motor and the deck portion upon which the motor is mounted.

12. A machine as claimed in claim 3 wherein the work head is provided in a floating work head assembly comprising the work head and motor as a unit, the assembly being suspended from the deck portion.

13. A machine as claimed in claim 12 wherein biasing means are operative between the deck and the assembly so that the assembly tilts and the work head is biased into enhanced contact with the floor.

14. A machine as claimed in claim 1 wherein the base portion is provided with wheel means to enable translational motion of the machine over the floor surface.

15. A machine as claimed in claim 14 wherein the wheel means comprises a single central wheel or roller, or two transversely spaced apart wheels or rollers.

16. A machine as claimed in claim 14 wherein, in a use configuration, the weight of the machine is shared by the wheel means and the work head or heads.

17. A machine as claimed in claim 14 wherein the wheels means are disposed at a rear region of the base portion, and the work head is disposed at a front region of the base portion.

18. A machine as claimed in claim 1 which is configured as a scrubber drier with scrubbing brush attachments provided on an underside of each work head, a cleaning liquid reservoir, a cleaning liquid dispenser provided in advance of, or under, the work head.

19. A machine as claimed in claim 18 further comprising a suction squeegee device for collecting liquid-entrained dirt and configured to be trailed behind the work head.

20. A machine as claimed in claim 1 wherein the transverse tilt is in an amount of 1 to 3 degrees, preferably 1.5 to 2.5 degrees away from the vertical.

21. A machine as claimed in claim 2 wherein the backwards tilt is in an amount of 1 to 3 degrees, preferably 1.5 to 2.5 degrees.

22. A machine as claimed in claim 1 wherein the handle portion is connected to the base portion by a universal joint.

23. A machine as claimed in claim 22 wherein the universal joint comprises two orthogonal pivots which permit up-down pivoting and side-to-side pivoting of the handle portion.

24. A machine as claimed in claim 22 wherein the universal joint connection is disposed at a rear end region of the base portion so as to facilitate walk-behind guiding of the machine by a user holding the handle portion distal end region.

25. A machine as claimed in claim 24 wherein the universal joint connection is adjacent the wheel means or incorporates the wheel means so that the weight of the handle portion and any associated components is mostly taken by the wheel means.

Description

[0030] In the drawings:

[0031] FIG. 1 is a three quarter perspective view of a floor scrubber-dryer machine in accordance with the present invention.

[0032] FIG. 2 is a side view of the configuration of the machine of FIG. 1 shown on a floor surface.

[0033] FIG. 3 is a side view of the base portion of the machine, with housing removed to show internal components, with defined Y and Z spatial directions, and a work head axis of rotation which is tilted from the vertical in the ?Z direction.

[0034] FIG. 4 is a front view of the base portion of FIG. 3, with defined X and Y directions, the and a work head tilted from the vertical in the ?X direction.

[0035] FIG. 5 is a three quarter perspective view from above of the base portion of the machine, with defined X, Y and Z directions.

[0036] FIG. 6 is an underside plan view of the base portion of the machine.

[0037] FIG. 7 is a side view of the scrubber drying machine, tilted back so as to lift the work head and base portion away from the floor, rotated about the rear wheels of the machine.

[0038] FIG. 8 shows an alternative embodiment of the machine in which the squeegee suction collection is disposed so as to trail behind the rear of the machine.

[0039] The scrubber-dryer machine in accordance with the invention is shown in FIG. 1 as 10. The machine includes a base portion 11, comprising a motor housing 2, a disc-shaped work head 4 (best seen in FIG. 6) and a squeegee suction collector 5 which has leading and trailing curved squeegee blades 43, 44 which together define a suction chamber therebetween. The squeegee is collector is disposed immediately behind the work head and has a span which equals or exceeds the diameter of the work head. The squeegee collector is supported by two transversely spaced apart trailing rollers 47 (see FIG. 6), which prevent the squeegee blades from collapsing under the weight of the collector. An upper portion of the squeegee collector is formed with a suction orifice 6 in fluid communication with a suction turbine (not shown) and a waste liquid collection tank (not visible). The work head has a lower side provided with an annular detachable brush unit 20 made up of a multitude of floor-facing bristles for agitating the floor surface.

[0040] In an alternative embodiment the squeegee collector is disposed behind the machine base portion, and specifically behind the rear wheels 45, as shown on FIG. 8.

[0041] There is an upstanding elongate handle portion 41 (see FIG. 6) with a cross bar 42 at an upper end region thereof, and the usual controls such as on/off and any work head speed control. A mid-region of the handle portion carries superstructure 7 within which is provided a cleaning liquid reservoir (not visible) and the waste liquid collection tank. The superstructure also carries at a lower end region thereof a re-chargeable battery which serves as a power supply.

[0042] A lower end region of the handle portion is attached to the base portion via a universal joint 30. The universal joint comprises an upper handle pivot P-P which permits side-to-side pivoting of the handle portion, and a lower, transverse pivot A-A which permits up and down pivoting of the handle. The user twisting the cross bar in a clockwise or counter-clockwise direction steers the base portion as it travels over a floor surface in a working direction W. Rotation of the work head causes the brushes 20 to scrub the floor. Cleaning liquid delivered to the floor in advance of the work head, or through a hub of the work head, assists in the cleaning effect. The dirty cleaning fluid is then collected behind work heads by the squeegee collector and discharged into the waste tank in the handle super structure (for subsequent disposal).

[0043] A rear end region of the base portion is provided with two co-axially mounted wheels 45 which support the weight of the handle portion, and the rear region of the base portion 11. The wheels have a fixed axis of rotation, so provide directional stability in the working direction of use W during use, whilst permitting steering by yawing of the base portion about the rear wheels 45.

[0044] In FIG. 3 the interior or the base portion 11 and associated components are shown. There is a substantially horizontal deck portion 48. The deck carries a motor drive unit 13. The motor drive unit comprises a generally cylindrical upright electric motor 15. The motor rotor is mated to a transmission unit (gearbox assembly) 16. A driven hub 14 (FIG. 6) depends from an underside of the gearbox assembly for driving the work head 4. The gearbox has an output shaft from which the hub depends. This output shaft is oriented so as to exhibit the rearwards tilt of 1.5 to 2.0 degrees from the vertical axis V, in the negative Z direction, as shown in FIG. 3. The output shaft is also oriented to give a tilt of 1.5 to 2.0 degrees from the vertical axis V in the transverse direction negative X, as shown in FIG. 4. The tilting can be conveniently achieved by the use of spacers, washers or wedges (not shown in the figures) disposed under one or more of the corners 50 of the gearbox assembly housing, above the associated deck upon which the gearbox assembly is mounted. In this way the whole gearbox assembly is tilted from the horizontal, producing a corresponding shift from the vertical of the output shaft which carries the hub and work head.

[0045] The combination of transverse tilt and backwards tilt of the work head produces increased pressure on the floor surface due to the biasing of the brush bristles in the bottom left region of the work head (as viewed in FIG. 6). The cross-hatched region indicates increased pressure due to tilting. The backwards and transverse tilts of the brushes produces increased pressure around the 10 o'clock to 4 o'clock positions of the work head. The work head rotation direction (counter-clockwise in FIG. 6) means that there is increased traction in the biased region, and this produces a propulsive reaction. The rearward tilt helps correct the propulsive thrust so as to be substantially forwards in the working direction, albeit with a small amount of curve which would tend to produce a tendency to steer to the right, but which can be easily correct by the user/operator.

[0046] The rearward biasing of the work head also compresses the brush bristles and helps retain cleaning liquid within the confines of the annular work head brushes. The biasing of course improves the agitation effect and aids cleaning. The rearward biasing improves the agitation effect across almost the entire span of the work head/brush.

[0047] The handle portion is preferably connected to the base portion by a universal joint. The universal joint may comprise two orthogonal pivots which permit up-down pivoting and side-to-side pivoting of the handle portion. The universal joint connection is preferably disposed at a rear end region of the base portion. This facilitates walk-behind guiding of the machine by a user holding the handle portion distal end region. Steering involves twisting the handle portion clockwise or anti-clockwise. The universal joint connection may be adjacent the wheel means (when present) so that the weight of the handle portion and any associated components is mostly taken by the wheel means, whereas the work head takes the weight of the motor/transmission.

[0048] In summary, the invention provides a hand-guided floor treatment machine comprising a handle portion connected to a base portion, which base portion is provided with a rotatable generally disc-shaped floor-facing work head having a substantially vertical axis of rotation, the machine being provided with drive means for rotatably driving the work head, wherein the rotational axis of the work head is slightly tilted away from the vertical in a direction which has a transverse component and a rearward component so that the work head is biased into contact with the floor in a region rearwardly and to one side of the work head, whereby in use rotation of the work head through the biased region provides propulsion predominantly in a forward direction.