Floor treatment machine

Abstract

A hand-guided floor treatment machine (10, fig 1) comprises a base portion (11, fig 1) which carries at least one motor-driven floor-facing treatment tool (12, fig 1) and an elongate upright handle portion (20, fig 1) which has an upper end region provided with a hand grip (21, fig 1) for guiding the machine in a working direction, wherein a lower end region of the handle portion is provided with a first pivot joint 126 having a transverse axis of rotation which permits the handle portion to incline up or down in an arc oriented fore-aft, and wherein there is a second pivot joint 117 having an axis of rotation oriented fore-aft, the second pivot joint permitting the handle portion to move laterally from side-to-side about the fore-aft axis, with the first and second pivot joints arranged to form a Cardan joint 40 operable between the handle portion and the base portion and configured so as to permit steering of the base portion by user twisting of the handle portion. The axis of rotation of the second pivot joint is disposed vertically below the axis of rotation of the first pivot joint.

Description

In accordance with the present invention there is provided a floor treatment machine equipped with a novel Cardan joint arrangement and a handle locking arrangement which makes the machine more convenient to use. In accordance with the present invention there is provided a hand-guided floor treatment machine comprising a base portion which carries at least one motor-driven floor-facing treatment tool, and an elongate upright handle portion which has an upper end region provided with a hand grip for guiding the machine in a working direction, wherein a lower end region of the handle portion is provided with a first pivot joint having a transverse axis of rotation which permits the handle portion to pivot up or down in an arc oriented fore-aft, and wherein there is a second pivot joint having an axis of rotation oriented fore-aft, the second pivot joint permitting the handle portion to move laterally from side-to-side about the fore-aft axis, characterised in that the axis of rotation of the second pivot joint is disposed vertically below the axis of rotation of the first pivot joint with the first and second pivot joints arranged to form a Cardan joint operable between the handle portion and the base portion and configured so as to permit steering of the base portion by twisting of the handle portion US2012 / 0279010 (Kenter) discloses a hand-guided floor scrubber-drier treatment machine having an upright handle portion which is provided with two mutually orthogonal pivots attach the handle portion to the base portion. These pivots allow the user to steer the work head (base portion) left and right by twisting the handle around its longitudinal axis. One problem with this machine is it relies upon counter-rotating floor treatment discs. If the discs are not perfectly balanced with respect to each other then it may drift or veer away from the intended path. Because the weight of the machine is taken exclusively by the scrubbing bristles, it is sometimes not possible to shift dirt on the floor surface without deforming the scrubbing bristles. The present invention seeks to address these problems. The invention provides a machine which allows the user to impose more downward force from time to time, so as to enhance the cleaning action from time to time. According to one aspect of the present invention there is provided a hand-guided floor treatment machine comprising a base portion which carries at least one motor-driven floor-facing treatment tool, and an elongate upright handle portion which has an upper end region provided with a hand grip for guiding the machine in a working direction, wherein a lower end region of the handle portion is provided with a first pivot joint having a transverse axis of rotation which permits the handle portion to incline up or down in an arc oriented fore-aft, and wherein there is a second pivot joint having an axis of rotation oriented fore-aft, the second pivot joint permitting the handle portion to move laterally from side-to-side about the fore-aft axis. The first and second pivot joints may be arranged to form a Cardan joint operable between the handle portion and the base portion and configured so as to permit steering of the base portion by user twisting of the handle portion. The invention may be characterised in that the axis of rotation of the second pivot joint is disposed vertically below the axis of rotation of the first pivot joint. The vertical separation between the axes provides a mechanical moment which allows the user to apply downward pressure on the scrubbing tool / brush when a forwards pushing force P is applied via the reclined handle portion to the pivot axis B’. This results in a rotation forwards R as shown in figure 6 which increased the cleaning pressure on the underlying floor. Conversely, if the user pulls the handle portion back the rotation R is reversed and the weight on the scrubbing tool / brush is reduced, which makes the machine easier to move in a return stroke. This makes the machine easier to use. The Cardan joint comprises an upwardly directed yoke the two arms of which provide said first transverse pivot axis, and wherein a lower end of the yoke is attached to the base portion by the second fore-aft pivot axis which permits the entire yoke to move from side-to-side during steering of the machine using the upright handle portion. The first pivot joint may comprise an upper axle which passes through corresponding co-axial bores provided in the yoke arms. The second pivot joint may comprise a one or two upstands (on the base portion top side) which receive a lower axle. The yoke may comprise a member having two generally vertically projecting arms with the first pivot axis formed therebetween. There may be a depending projection which is attached to the base portion by the second axis (or its axle). The depending projection may be arcuate in shape with a bore formed therein. The first and second axes may each be defined by respective first and second axles located in bores through the yoke. The floor treatment tool comprises a floor-facing disc-shaped tool. The handle portion my be provided with a cleaning liquid reservoir. In this case means are provided for delivering cleaning liquid to the floor tool to provide wet cleaning. The machine may be provided with a waste water collection tank. In this case there may be provided a suction collector for lifting waste liquid from the floor and conveying the waste liquid to the collection tank. Squeegee suction collectors are known in the art. The suction collector may comprise a floor-facing trailing squeegee collector disposed behind the floor tool (or tools) in the normal direction of cleaning. The first pivot joint may be provided with a first lock mechanism which immobilises the handle portion against fore-aft movement. The second pivot joint may be provided with a second lock mechanism which immobilises the handle portion against side-to-side movement. The handle locked position corresponds to a substantially vertical handle portion orientation. Each lock mechanism may comprise an arrangement whereby a locking block and corresponding recess engage with each other so as to prevent free pivoting in each associated pivot axis. A single moveable member may be provided with locking blocks for immobilising both pivots by a single movement of the member from an unlocked to locked position. The treatment machine may be provided with guide wheels or rollers which assist directional stability. Typically the weight of the machine is shared between the treatment head (brush) and the wheels. Retractable wheels may be provided which may be deployed for transport between cleaning tasks. Following is a description, by way of example only and with reference to the drawings hereinafter of one mode for putting the invention into effect. In the drawings:- Figure 1 is a side view of a floor scrubbing machine in accordance with the present invention. Figure 2 is a perspective three quarter view of a base portion of the floor scrubbing machine of figure 1. Figure 3 is a perspective three quarter view of a Cardan joint by which the machine upright portion is attached to the base portion. Figure 4 is a perspective three quarter exploded view of the Cardan joint of figure 3. Figure 5 is a perspective three quarter exploded view of figure 4 but rotated 90 degrees about its vertical axis. Figure 6 is a schematic representation of the mechanics of the floor scrubbing machine when pushed along a cleaning path. In figure 1 the scrubbing machine is shown generally at 10, placed on a floor surface 9. There is a base portion 11 provided at a front region thereof with a floor-facing disc-shaped floor scrubbing attachment 12. The attachment has a lower surface provided with a covering of bristles (or other scrubbing / abrasive media) 13 which agitate a surface being cleaned when the machine is in use. The scrubbing attachment is driven to rotate by an electric motor (not visible) within housing 14. At a rear region of the base portion is a pair of transversely spaced apart support wheels (one visible as 15). The weight of the machine is shared by the support wheels and the scrubbing attachment. To the rear of the support wheels is a squeegee suction collector assembly 16 which is of conventional construction, having a pair of transversely extending curved squeegee blades 17, best seen in figure 2. The squeegee collector assembly is supported by trailing wheels or rollers 30 A front region of the base portion is provided with two spaced apart transport wheels (one visible as 18) which are in the working configuration raised from the floor surface and above the scrubbing attachment. The transport wheels are carried by a front housing portion 19 which can be shifted downwards to cause the transport wheels to deploy to contact the floor surface. The rear wheels are arranged to concurrently deploy along with the front transport wheels by means of rods, pivots and cams, with all four wheels (15, 18) then acting to keep the scrubbing attachment off the floor. Returning to figure 1 the machine has an elongate rectangular section upright portion 20 which has at an upper end region thereof a handle 21 (with cross bar) and control console 22. The upright portions carry superstructure including a battery compartment 24, a cleaning liquid reservoir and a waste water tank 25. The waste water tank is fed by the suction assembly 16 via a concertina hose 26 which draws fluid up from the suction collector assembly and discharges into the waste water tank 25. The cleaning liquid reservoir delivers cleaning liquid via the scrubbing attachment through a central hole in a hub (not shown) of the scrubbing attachment. The liquid falls (or is pumped) into the hub and down onto the floor beneath the scrubbing attachment, in order to assist in the cleaning action of the scrubbing bristles (or other treatment media). The dirty liquid formed from the cleaning action is sucked into the collector via concertina hose 26 and delivered into the waste tank. The tank is typically removeable so as permit easy disposal in a sink or drain. The upright tube 26 is attached to the base portion by a Cardan joint 40. The joint is shown in more detail in figure 3 which is a perspective three quarter exploded view of the Cardan joint 40 in accordance with the present invention. The joint comprises a lower flat bracket 111 which supports two upstanding spaced apart cheek plates 112,113. Each cheek plate has the form of an isosceles triangle formed with vertical ribs 114. A central region of each cheek plate is formed with a through bore 115, 116, best seen in figure 4. The two bores receive a cheek axle (117 in figure 3) which has a fore-aft alignment along axis A’ in figure 3. Above the cheek plates is a cradle member 118 which has two upstanding spaced apart, opposing yoke arms 119, 120. Each yoke arm has a semicircular upper region provided with a yoke bore 211,122. The two yoke bores receive a yoke axle (126 visible in figure 3 which is aligned transversely with respect to the cheek axle 117 of the cheek plates. A lower region of the cradle member 118 is provided with a depending triangular nub 124 which is formed with a nub bore 125. The nub is accommodated in the valley 129 defined between the upstanding cheek plates. The nub has a bore 125 through which the cheek axle 117 passes. The cheek axle thus provides a pivoting joint by which the cradle member and associated yoke arms can rotate from side to side about the rotation axis A defined by the cheek axle 117. A lower floor 127 of the cradle member has a generally arcuate and concave form. An upper region of the lower floor is formed with axial channels 128 in moulding 134, which receive corresponding latching blocks 131, 132 to lock the yoke member against rotation about the yoke axle 126 along axis B’. The yoke arms 120, 119 receive therebetween a lower region of the upright handle 26. The handle comprises a rectangular section metal tube 26. The lower region of the handle is provided with a two elongate side-by-side blocks 131, 132. These two blocks are substantially parallel with respect to each other, and parallel with respect to yoke pivot axis B’. These blocks can be engaged with the respective axial channels 128 so as to immobilise the handle against pivoting with respect to the yoke cradle. .A further block feature depends from the moulding 134. The block feature can engage with a cut-out portion 130 of the upper end of the upstands 112,113. This engagement locks the cradle against pivoting about the upstands in a side-to-side manner about axle A’. Thus, the handle 26 can be immobilised against pivoting around either axis A or B’ away from the vertical. Engagement can be achieved or assisted by biasing the moulding (locking member) 134 downwards towards the bottom of the yoke cradle so that the blocks move into engagement. The blocks 131, 132 and 133 can all move together as they are disposed on the same moulding (or member) 134. Thus, handle locking against pivoting in both fore-aft and side-to-side orientations can be effected in a singular movement, keeping the handle in vertical orientation for travel, storage or emptying the waste tanks. Release of these pivot locks can also be effected simply in a single action by upwards (retreating) travel of the moulding or member 134. The Cardan joint permits the upright handle to be reclined about pivot axis B’ to a comfortable working height for the user walking behind the machine. The upright handle can also be move from side to side about pivot axis A. This provides a steering effect which makes the base portion very manoeuvrable. By twisting of the handle portion around its own longitudinal axis the base portion can itself be rotated from left to right. By placing the fore-aft pivot vertically above the side-to-side pivot the base portion does not foul the lower end region of the upright handle portion when the handle portion is moved fore-aft. Furthermore, the side-to-side pivot, disposed low in the base portion, allows enough pivoting movement of the handle to permit a good steering effect, without the handle portion fouling on the base portion / housing. As discussed above, and with reference to figure 6, the invention may be characterised in that the axis of rotation of the second pivot joint is disposed vertically below the axis of rotation of the first pivot joint. The vertical separation between the axes provides a mechanical moment which allows the user to apply downward pressure on the scrubbing tool / brush when a forwards pushing force P is applied via the reclined handle portion to the pivot axis B’. This results in a rotation forwards R as shown in figure 6 which increased the cleaning pressure on the underlying floor. Conversely, if the user pulls the handle portion back the rotation R is reversed and the weight on the scrubbing tool / brush is reduced, which makes the machine easier to move in a return stroke. This makes the machine easier to use. The separation is in some embodiments between about 50 and 100 mm.

Claims

1. A hand-guided floor treatment machine comprising a base portion which carries at least one motor-driven floor-facing treatment tool, and an elongate upright handle portion which has an upper end region provided with a hand grip for guiding the machine in a working direction, wherein a lower end region of the handle portion is provided with a first pivot joint having a transverse axis of rotation which permits the handle portion to incline up or down in an arc oriented fore-aft, and wherein there is a second pivot joint having an axis of rotation oriented fore-aft, the second pivot joint permitting the handle portion to move laterally from side-to-side about the fore-aft axis, with the first and second pivot joints arranged to form a Cardan joint operable between the handle portion and the base portion and configured so as to permit steering of the base portion by user twisting of the handle portion,the invention being characterised in that the axis of rotation of the second pivot joint is disposed vertically below the axis of rotation of the first pivot joint.

2. A treatment machine as claimed in claim 1 wherein the Cardan joint comprises an upwardly directed yoke the two arms of which provide said first transverse pivot axis, and wherein a lower end of the yoke is attached to the base portion by the second fore-aft pivot axis which permits the entire yoke to move from side-to-side during steering of the machine using the upright handle portion.

3. A treatment machine as claimed in claim 1 or 2 wherein the first pivot joint comprises an upper axle which passes through corresponding co-axial bores provided in the yoke arms.

4. A treatment machine as claimed in any of claims 1 to 2 wherein the second pivot joint comprises a one or two upstands which receive a lower axle.

5. A treatment machine as claimed in claim 2 wherein the yoke comprises a member having two generally vertically projecting arms with the first pivot axis formed therebetween, and a depending projection which is attached to the base portion by the second axis.

6. A treatment machine as claimed in claim 5 wherein the first and second axes are each defined by respective first and second axles located in bores through the yoke.

7. A treatment machine as claimed in any of the preceding claims wherein the floor treatment tool comprises a floor-facing disc-shaped tool.

8. A treatment machine as claimed in claim 7 wherein the handle portion is provided with a cleaning liquid reservoir and wherein means are provided for delivering cleaning liquid to the floor tool to provide wet cleaning.

9. A treatment machine as claimed in any of the preceding claims wherein the machine is provided with a waste water collection tank and a suction collector for lifting waste liquid from the floor and conveying the waste liquid to the collection tank.

10. A treatment machine as claimed in claim 8 wherein the suction collector comprises a floor-facing trailing squeegee collector disposed behind the floor tool or tools in the normal direction of cleaning.

11. A treatment machine as claimed in any of the preceding claims wherein thefirst pivot joint is provided with a first lock mechanism which immobilises the handle portion against fore-aft movement.

12. A treatment machine as claimed in any of the preceding claims wherein the second pivot joint is provided with a second lock mechanism which immobilises the handle portion against side-to-side movement.

13. A treatment machine as claimed in claim 11 or 12 wherein the handle locked position provides a substantially vertical handle portion orientation.

14. A treatment machine as claimed in any of claims 11 to 13 wherein each lock mechanism comprises an arrangement whereby a locking block and corresponding recess engage with each other so as to prevent free pivoting in each associated pivot axis.

15. A treatment machine as claimed in any of claims 11 to 14 wherein a single moveable member is provided with locking blocks for immobilising both pivots by a single movement of the member from an unlocked to locked position.13

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