FLOOR TREATMENT MACHINE

Abstract

A floor cleaning machine has one or more work heads, one or more motors for driving one or more work heads via a transmission unit for each work head, wherein each transmission unit has a drive shaft with a co-axial chuck for releasably engaging with the associated work head to rotate the work head. The machine has a liquid reservoir, and at least one liquid conduit extending from the reservoir towards a transmission unit of one of the work heads. The drive shaft has a co-axially extending through-bore receiving a liquid feed tube, the feed tube providing a liquid path for treatment liquid through the transmission unit and through the work head, the feed tube having an upper region for receiving liquid from the conduit and a lower region which feeds through the work head to serve as an outlet for delivering liquid to the underside of the work head.

Description

The present invention relates to the field of floor treatment machines and in particular floor cleaning or polishing machines. Particularly the invention relates to floor cleaning or polishing machines which comprise disc-shaped work heads for scrubbing a floor surface with the assistance of a treatment liquid.

Such machines typically deliver treatment liquid to the floor from a reservoir housed in the machine. The treatment liquid is then used in scrubbing the floor using rotating disc shaped work heads equipped with scrubbing bristles or polishing pads. Dirty liquid is collected from the rear of the machine by a suction collector, typically using a squeegee trailed behind the work heads.

Conventionally, floor treatment machines apply treatment liquid in front of the work heads. Using this method is wasteful as liquid tends to spread beyond the confines of the work heads and their associated scrubbing bristles.

The present invention seeks to provide a floor cleaning or polishing machine which makes better and more targeted use of treatment liquid.

According to one aspect of the invention there is provided a floor cleaning or polishing machine comprising one or more generally disc-shaped, floor-facing work heads for treating the floor surface, one or more motors for driving the one or more work heads via a transmission unit for each work head. Each transmission unit provides a generally vertical drive shaft which is provided at a lower end region thereof with a co-axial chuck for releasably engaging with the associated work head so as to rotate the work head in use.

The machine is provided with a treatment liquid reservoir, and at least one liquid conduit extending from the reservoir towards a transmission unit of one of the work heads. The drive shaft is provided with a co-axially extending through-bore in which is received a generally vertically oriented liquid feed tube. The feed tube provides a liquid path for treatment liquid through the transmission unit and through the associated work head.

The feed tube has an upper region for receiving treatment liquid from the liquid conduit and a lower region which feeds through the work head so as to serve as a treatment liquid outlet for delivering treatment liquid to the under side of the work head.

By delivering the treatment liquid directly to the floor opposite the underside of the work head, the liquid is largely constrained within the confines of the work head. This means that all the applied liquid can take part in the cleaning process. The pressure applied to the bristles by the weight of the machine helps to retain the liquid. As the machine moves forwards in a treatment direction, the treatment liquid (typically a detergent solution) disperses in the brush or pads of the work head and can then be collected.

The motor of the machine may have a rotor which engages with and drives the transmission. The rotor may be generally vertically oriented and offset with respect to the transmission drive shaft axis. In this way the motor does not block access to the through bore of the drive shaft,

The feed tube may comprise a rigid member. The feed tube may be tapered so as to narrow towards the work head end thereof. The feed tube may have an outer surface which is spaced apart from the through bore inner surface. An upper region of the feed tube may project above the transmission unit. The feed tube upper region may be provided with a manifold for containing treatment liquid which is to be fed into the feed tube.

An externally projecting stub tube may be provided which feeds into the manifold. The stub tube is engaged with a flexible supply tube from the reservoir.

The upper region of the feed tube may be provided with a pump and/or valve for controlling liquid feed into the tube. The valve may be a solenoid valve.

Each work head of the machine may be driven by an assembly comprising one transmission unit including a drive shaft carrying the chuck, a motor offset from the drive shaft axis and including a rotor which engages with the transmission, and a liquid feed tube accommodated in the drive shaft through bore.

An upper region of the feed tube may project above the transmission unit. The feed tube upper region may be provided with a manifold for containing treatment liquid which is to be fed into the feed tube.

Each work head may be biased to adopt a tilted orientation during use, so that one portion of the work head is depressed and urged against the floor being treated or scrubbed. This may be achieved by tilting the rotational axis of the work head away from the vertical by a few degrees, in practice about 2 to 5 degrees. In a preferred arrangement the axis is tilted back (i.e., towards the machine rear) so that a rear portion of each work head is subject to biasing pressure. This helps retain treatment liquid in the central region of the work head underside which received the treatment liquid.

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

In the drawings:

FIG. 1 is a side view of a floor cleaning or polishing machine in accordance with the invention.

FIG. 2 is a perspective three-quarter view of a deck assembly in accordance with the invention, shown without a housing.

FIG. 3 is a side section view through the deck assembly of FIG. 2

FIG. 4 is an exploded perspective view of a motor assembly in accordance with the invention

FIG. 5 is a perspective view of a valve and feed tube assembly in accordance with the invention

FIG. 6 is a section view of the valve and feed tube assembly of FIG. 5

A floor cleaning or polishing machine is shown generally as 1 in FIG. 1. The machine 1 comprises a deck assembly 2, a machine upper housing 3, a support shaft 4 and a handle portion 5 which comprises operating controls. The machine housing 3 encloses feed and waste liquid reservoirs (not visible) for supply and return of liquid to and from a cleaning surface via a pair of generally disc shaped floor-facing scrubbing pads 6, 7 and a feed conduit 8 and return suction conduit 9. The scrubbing pads 6, 7 are mounted to corresponding generally disc shaped pad holders 43, 44 to form a work head assembly.

The support shaft 4 connects the handle portion 5 to the machine housing 3, the machine housing 3 being mounted on a central region of the support shaft 4. The support shaft 4 connects the machine housing 3 to the deck assembly 2 via a pivotal linkage 10 located at a lower end 11 of the support shaft 4. The linkage 10 is configured to allow both fore/aft and side to side pivoting of the shaft support 4 with respect to the deck assembly 2.

A rear support frame 12 trails the deck assembly 2 to the rear of the floor scrubber 1. A squeegee collector 13 is connected to the rear support frame 12. The squeegee collector 13 is of a type known in the art and comprises a suction connector (9). In use the floor is wet scrubbed, and any dirt or detritus dissolved or entrained in the liquid. The excess liquid or detritus is collected by the squeegee collector 13 and returned to the machine waste reservoir 3 via the suction connector and return conduit 9. A trailing wheel 14 helps to support the weight of the squeegee collector without causing the squeegee blade to collapse under the weight of the collector. A foot pedal 15 is operably linked to the rear support frame 12 such that if a user presses the foot pedal with their foot the rear support frame 12 (including the squeegee collector) is lifted from the cleaning surface. This is beneficial for transport and storage.

Two horizontally spaced apart support wheels 16 (only one shown) are mounted to an underside of the rear support frame 12 and share the weight of the machine between the support wheels 16 and the cleaning pads 6, 7.

The deck assembly 2 in FIG. 2 comprises a deck housing 17 and a motor housing 18 which encloses multiple components. Details of the components enclosed in the deck and motor housings are shown in FIGS. 2 to 6.

The deck assembly comprises a first and second motor 19, 20, a first and second gearbox transmission unit 21, 22 operably connected to the corresponding first and second motors 19, 20. The first and second transmission units 21, 22 each comprise a generally vertical drive shaft 41, 42 provided at a lower end region thereof, as shown in FIG. 3. Each drive shaft 41, 42 comprises a coaxially extending through-bore. First and second solenoid valves 23, 24 are connected to respective first and second liquid delivery manifolds 25, 26. The solenoid valves are of a type known in the art and commonly used for shutting off liquid flow in liquid delivery systems. Each solenoid valve is provided with electrical connections 35 which are linked to the user controls to enable actuation of the valve. The solenoid valves 23, 24 may include pumping systems for pumping treatment liquid through the liquid delivery manifolds 25, 26 to the treatment surface. Alternatively, the solenoid valves may be gravity fed without the use of a pump. The first and second liquid delivery manifolds 25, 26 are mounted to a central region of the upper face of each of the corresponding transmission units 21, 22 via two feet 36, 37, 38, 39. The mounting feet 36, 37, 38, 39 extend downwards from the liquid delivery manifolds 25, 26 and provide connecting points in the form of through holes 51, 52, 53, 54 configured to be used with fasteners such as bolts.

FIGS. 4, 5 and 6 show the liquid delivery assemblies. Each liquid delivery manifold 25, 26 in provided with a liquid inlet 27, 28 which receives treatment liquid fed from the liquid reservoirs via the liquid conduits 8. The liquid inlets 27, 28 are generally cylindrical stub tubes extending from the liquid delivery manifolds 25, 26. The liquid inlets 27, 28 comprise a plurality of collars 30 tapered towards the open end which allow a liquid delivery conduit to be attached. liquid enters the liquid delivery manifold 25, 26 through the liquid inlets 27, 28. Each solenoid valve 23, 24 is configured to block or unblock the corresponding liquid delivery manifold 25, 26 when activated to control liquid flow through each manifold 25, 26.

Protruding generally vertically downwards from each liquid delivery manifold 25, 26 is a generally cylindrical feed tube 31, 32. Each feed tube 31, 32 is connected at a proximal end 29 to the corresponding liquid delivery manifold 25, 26. Each feed tube 31, 32 is open ended at each distal end, thus forming a liquid outlet 33, 34. The feed tube is preferably made from a corrosive resistant material. The corrosive material of each feed tube may be a plastic. Each feed tube may be tapered such that the diameter at the liquid outlet 33, 34 is smaller than the diameter at the connecting proximal end 29 of the feed tube. Each feed tube 31, 32 may be configured to locate within the corresponding drive shaft with the outer surface of the feed tube spaced apart from the inner surface of the through bore in the associated drive shaft. In such a configuration rotation of the drive shaft would not cause friction between the outer surface of the feed pipe and the inner surface of the through bore of each drive shaft.

FIG. 3 is a cross section A-A showing a side view through one half of the deck assembly 2. The view shows a section passing through a transmission drive shaft 41, 42. Each drive shaft 41, 42 passes vertically through the centre of each transmission unit 21, 22. Each drive shaft 41, 42 passes through a circular cut-out (not visible) spaced apart on opposite sides of the deck housing 17 into a region below the deck housing 17 which encloses the brush pads 6, 7.

The feed tubes 31, 32 locate within the drive shafts 41, 42 and run coaxially through the drive shafts 41, 42. Each feed tube 31, 32 extends from the liquid delivery manifolds 25, 26 through the associated work head. In this configuration treatment liquid is fed from the treatment liquid reservoirs, through the liquid conduits 8 into the liquid inlets 27, 28 of the liquid delivery manifolds 25, 26. The solenoid valves 23, 24 control the flow of the treatment liquid into the feed tubes 31, 32 via the liquid delivery manifolds 25, 26. Treatment liquid exits the feed tubes 31, 32 through the liquid outlets 33. Mounting the solenoid valves 23, 24 as close as possible to liquid outlets 33, 34 reduces excess liquid drips from the feed tubes after the machine is switched off.

The liquid outlets 33, 34 of each feed tube 31, 32 deliver treatment liquid to an enclosed inner region 40 of the brush pads 6, 7 (see FIG. 3). Delivery of treatment liquid to the inner region 40 of the brush pads 6, 7 reduces the amount of treatment liquid required compared to delivering treatment liquid outside the perimeter of the brush pads 6, 7. This provides more efficient and more economic floor treatment. With the drive shaft 41 axis tilted back by about 3-4 degrees, as shown in FIG. 3, the rear portion 57 of the work head assembly is depressed and biased against the floor. Water entering via the feed tube 31 and outlet 27 moves rearwards (in the direction of the arrows) towards the depressed work head rear portion 57. The work head bristles are less able to let the treatment liquid pass through, thereby delaying the egress of liquid behind the work head. The biasing pressure on the work head also serves to enhance the cleaning effect of the work head. The rearward biasing and drive shaft axis tilt is helped by the rearward offset weight of the motor 19.

First and second brush chucks 47, 48 are fixed to the lower distal ends of each drive shaft 41, 42. Each brush chuck 47, 48 engages with a corresponding upper central recess in the cleaning pad holders 43, 44. Each brush chuck 47, 48 and brush chuck recess 45, 46 have corresponding octagonal profiles such that each brush chuck 47, 48 fits into each brush chuck recess 45, 46 and transfers rotational movement about a generally vertical central axis of the drive shafts 41, 42. Each drive shaft 41, 42 (and consequently the cleaning pads 6,7) is caused to rotate when the corresponding electric motors 19, 20 are active. A user may control the rotation of the cleaning pads 6, 7 and delivery of treatment liquid to the cleaning pads 6, 7 through the user controls located on the handle portion 5.

The present invention relates to the field of floor treatment machines and in particular floor cleaning and polishing machines. There is disclosed a floor cleaning or polishing machine comprising one or more generally disc-shaped, floor-facing work heads for treating the floor surface, one or more motors for driving the one or more work heads via a transmission unit for each work head, wherein each transmission unit provides a generally vertical drive shaft which is provided at a lower end region thereof with a co-axial chuck for releasably engaging with the associated work head so as to rotate the work head in use. The machine is provided with a treatment liquid reservoir, and at least one liquid conduit extending from the reservoir towards a transmission unit of one of the work heads. The drive shaft is provided with a co-axially extending through-bore in which is received a generally vertically oriented liquid feed tube, the feed tube providing a liquid path for treatment liquid through the transmission unit and through the associated work head, the feed tube having an upper region for receiving treatment liquid from the liquid conduit and a lower region which projects through the work head so as to serve as a treatment liquid outlet for delivering treatment liquid to the underside of the work head.

Claims

1. A floor cleaning or polishing machine comprising one or more generally disc-shaped, floor-facing work heads for treating the floor surface, one or more motors for driving the one or more work heads via a transmission unit for each work head, wherein each transmission unit provides a generally vertical drive shaft which is provided at a lower end region thereof with a co-axial chuck for releasably engaging with the associated work head so as to rotate the work head in use, wherein the machine is provided with a treatment liquid reservoir, and at least one liquid conduit extending from the reservoir towards a transmission unit of one of the work heads, and wherein the drive shaft is provided with a co-axially extending through-bore in which is received a generally vertically oriented liquid feed tube, the feed tube providing a liquid path for treatment liquid through the transmission unit and through the associated work head, the feed tube having an upper region for receiving treatment liquid from the liquid conduit and a lower region which feeds through the work head so as to serve as a treatment liquid outlet for delivering treatment liquid to the underside of the work head.

2. A machine as claimed in claim 1 wherein the motor has a rotor which engages with and drives the transmission, the rotor being generally vertically oriented and offset with respect to the transmission drive shaft axis.

3. A machine as claimed in claim 1 wherein the feed tube comprises a rigid member.

4. A machine as claimed in claim 3 wherein the feed tube is tapered so as to narrow towards the work head end thereof.

5. A machine as claimed in claim 3 wherein the feed tube has an outer surface which is spaced apart from the through bore inner surface.

6. A machine as claimed in claim 1 wherein an upper region of the feed tube projects above the transmission unit.

7. A machine as claimed in claim 6 wherein the feed tube upper region is provided with a manifold for containing treatment liquid which is to be fed into the feed tube.

8. A machine as claimed in claim 7 wherein an externally projecting stub tube is provided which feeds into the manifold.

9. A machine as claimed in claim 6 wherein the upper region is provided with a pump and/or valve for controlling liquid feed into the tube.

10. A machine as claimed in claim 1 wherein each work head is driven by an assembly comprising one transmission unit including a drive shaft carrying the chuck, a motor offset from the drive shaft axis and including a rotor which engages with the transmission, and a liquid feed tube accommodated in the drive shaft through bore.

11. A machine as claimed in claim 10 wherein an upper region of the feed tube projects above the transmission unit.

12. A machine as claimed in claim 11 wherein the feed tube upper region is provided with a manifold for containing treatment liquid which is to be fed into the feed tube.