Floor treatment machine joint

Abstract

A hand-guided floor treatment machine comprises a base unit which carries at least one motor-driven floor-facing treatment tool, and an elongate guide part which has an upper end region provided with

Description

The present invention relates to floor treatment machines such as floor scrubber driers, and particularly to a joint provided between a guide part and a base unit of a floor treatment machine. A hand-guided floor treatment machine typically comprises a base portion, and an elongate guide part or handle portion. The base portion may carry at least one motor-driven disc-shaped floor-facing treatment tool, and / or may comprise an agitating medium, such as brush bristles, wire bristles or abrasive paper or web. The machine may be provided with a tank assembly, comprising a cleaning liquid reservoir, and a waste liquid collection tank. During use of the machine, a user grips a handle provided at the end of the guide part, urges the machine in a forwards or reverse direction across a floor to be cleaned, and steers the machine by tilting the guide part in a forwards or backwards and / or side to side direction. Means are provided for delivering cleaning liquid from the cleaning liquid reservoir to the floor tool to provide wet cleaning. A suction collector is provided for lifting waste liquid from the floor and conveying it to the waste liquid collection tank. The suction collector comprises a floor-facing trailing squeegee collector assembly disposed behind the floor tool or tools in a normal direction of cleaning. The base unit may be attached to the guide part via a joint which enables the required forwards / backwards and side to side movement of the guide part relative to the base unit. An example of such is a connector a universal joint which enables the guide part to pivot relative to the base unit. Other known joints for connecting the guide part to the base unit comprise a flexible hollow member such as an elastomeric sleeve, or a coil spring. The present invention provides an improved joint for connecting a base unit of a floor treatment machine to a guide part. The present invention provides a substantially solid, i.e. non-hollow, flexible connection between the guide part and the base. The flexible connection can flex to achieve a required range of movement of the guide part relative to the base unit. According to a first aspect of the present invention there is provided a hand-guided floor treatment machine comprising a base unit which carries at least one motor-driven floor-facing treatment tool, and an elongate guide part which has an upper end region provided with a handle for guiding the machine in a working direction; wherein the base unit is connected to the guide part via a joint, the joint comprising a flexible member comprising a solid flexible core and wherein a spring is encased within the core, wherein flexing of the flexible member enables the guide part to be tilted relative to the base unit in a fore and aft, and a side to side direction. The flexible member and the internal spring enable flexing of the joint, allowing a fore / aft and a side-to-side movement of the guide part, whilst preventing any rotational I twisting movement of the flexible section, therefore enabling transmission of torque from the guide part to the base unit 4 during use of the machine. The joint may comprise an upper mount plate attached to a lower end region of the guide part, and a base mount attached to the base unit, and the flexible member may extend between the upper mount plate and the base mount plate. The spring may extend between an underside of the upper mount plate, and an upper surface of the base mount plate. The spring may comprises a high strength spring. The flexible member may comprises a rubber or a rubber-like material. The core may comprise a cylindrical shaft. The cylindrical shaft may be surrounded by an external sheath. The external sheath may, for example, be formed of a semi-rigid material, with a plurality of slots provided in the external sheath provide a plurality of living hinges allowing flexing of the flexible member. The living hinges enable flexing of the cylindrical flexible section, allowing a fore / aft and a side-to-side movement of the guide part, whilst preventing any rotational I twisting movement of the flexible section, therefore enabling transmission of torque from the guide part to the base unit during use of the machine. The slots may be provided on the external sheath a uniform pattern, i.e. in a consistent manner across the sheath. This enables consistent flexing across the flexible section. Alternatively, the external sheath may comprise a plurality of interlocked segments. The plurality of interlocked segments may comprise an uppermost segment rigidly attached to an underside surface of the upper mount plate, and a lowermost segment rigidly attached to an upper surface of the base mount plate, and a plurality of intermediate segments located between the uppermost segment and the lowermost segment. The combination of fixed uppermost and lowermost segments, and "floating" intermediate segments allows the flexible member to flex and allow a fore / aft and a side-to-side movement of the guide part, as the intermediate segments are able to separate to cope with stretching I flexing of the flexible member. When torque is applied, at least one side of the teeth of the segment will always be interlocked with an adjacent segment, therefore, allowing transmission of torque from the guide part to the base. The cylindrical shaft may be surrounded by a hose. The hose may have a smooth, spiral, or corrugated external profile. The hose may also have a smooth, spiral or corrugated internal profile. The hose may be formed of a plastic; for example the hose could be moulded from a PA6 plastic. Walls of the hose may be reinforced by embedded metal or engineering plastic reinforcement. When the hose is arranged around the internal cylindrical shaft and torque is applied to the joint, the hose prevents any twisting I rotation of the cylindrical flexible section. The hose and the cylindrical shaft therefore enable flexing of the cylindrical flexible section, allowing a fore / aft and a side-to-side movement of the guide part, whilst preventing any rotational I twisting movement of the flexible section, therefore enabling near instant transmission of torque with minimal lag from the guide part to the base unit during use of the machine. Without the internal cylindrical shaft, the hose would be susceptible to impact damage. During bending the cylindrical shaft prevents the hose from kinking by providing internal support. Flexing of flexible member may enable the guide part to be tilted with respect to the guide part within a cone-shaped or hemispherical locus of movement. For example, tilting of the guide part up to an particular angle from a horizontal direction may be enabled. Angles of less than 90° provides a cone-shaped locus of movement; an angle of 90°provides a hemispherical locus of movement. The joint may be configured to return the guide part to a vertical orientation under bias. The material(s) and configuration may be selected to provide a stiffness of the joint sufficiently low enough to allows tilting of the guide part when a user applies force to the handle, but sufficiently high to cause the joint to spring back to a non-flexed state when a user is not applying force to the handle, thereby return the guide part to a vertical I upright position. The machine may further comprise a locking mechanism comprising a locking member, movable between an unlocked position in which tilting of the guide part relative to the base unit is enabled, and a locked position in which tilting of the guide part relative to the base unit is prevented. The locking mechanism can be used to lock the guide part in a vertical I upright position when the machine is not in use. A joint with a lower stiffness can therefore be provided. The locking member may comprises a rigid collar, which in the unlocked position, is raised relative to the base unit and surrounds a lower end of the guide part, and which is lowerable towards the base unit thereby to move to the locked position in which the collar surrounds the joint. The locking mechanism may further comprises a locating means comprising a channel which receives a lower edge of the collar in the locked position. The machine may comprising a floor scrubber drier. In a further aspect, the present invention comprises a method of forming the joint a machine of the first aspect, the method comprising overmoulding a flexible material onto the spring. The method may further comprise providing an upper mount plate at an upper end of the joint, and providing a base mount plate at a lower end of the joint. The method may further comprise fixedly attaching a lower end of the guide part of the machine to an upper surface of the upper mount plate. The method may further comprise fixedly attaching an underside surface of the base mount plate to the base unit of the machine. Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. The invention will now be described, by way of example only, with reference the accompanying drawings in which: Figure 1 is a schematic side view of a machine in accordance with the present invention; Figure 2 is a schematic underside view of the machine of figure 1; Figures 3a, 3b and 3c are schematic side views of machines in accordance with the present invention with differing tank configurations; Figure 4a is a schematic side view of the machine of figure 1, with the handle portion displaced from an upright position; Figure 4b is a schematic rear view of the machine of figure 1, with the handle portion displaced from an upright position; Figures 5a, 5b and 5c are partial schematic front views of a machine in accordance with the present invention showing sequential steps of a method to lock the guide part; Figures 6a and 6b are schematic views of a joint of a machine in accordance with the present invention; Figure 7a is an isometric view of a first embodiment of flexible member in accordance with the present invention; Figure 7b is a side view of the flexible member of figure 7a; Figure 8a is a partially transparent isometric view of a second embodiment of flexible member in accordance with the present invention; Figure 8b is a partially transparent side view of the flexible member of figure 8a; Figure 8c is a cross-sectional view of the flexible member of figure 8b along the section A-A as indicated in Figure 8b; Figure 9a is an isometric view of a second embodiment of flexible member in accordance with the present invention; Figure 9b is a side view of the flexible member of figure 9a; Figure 9c is a cross-sectional view of the flexible member of Figure 9b along the section A-A as indicated in figure 9b; Figure 10a is an isometric view of a second embodiment of flexible member in accordance with the present invention; Figure 10b is a side view of the flexible member of figure 10a; Figure 10c is a cross-sectional view of the flexible member of figure 10b along the section A-A as indicated in figure 10b; Figures 10d and 10e are side views of hoses alternative hoses in accordance with the present invention; and Figure 10f is a schematic representation of a corrugated profile. Figure 1 illustrates a hand-guided floor treatment machine 2 comprising a base unit 4, and an elongate guide part or handle portion 6. The base portion 4 carries a floor-facing treatment tool 8. As illustrated in figure 2, the floor-facing treatment tool 8 comprises two disc-shaped tools 10,12, arranged for counter-rotation, i.e. in the direction R1 and R2 respectively. The floor-treatment tool 8 may alternatively or additionally comprise an agitating medium, such as brush bristles, wire bristles or abrasive paper or web. Referring to figures 3a, 3b and 3c, the machine 2 is provided with a tank assembly 14 (illustrated in figures 3a, 3b and 3c), comprising a cleaning liquid reservoir, and a waste liquid collection tank. Various configurations of the tank assembly 14 are possible. For example, figure 3a shows the tank assembly 14 attached to the base unit 4, figure 3b shows the tank assembly 14 attached to the base unit 4, and figure 3c shows the tank assembly 14 split between the base unit 4 and the guide part 6, i.e. one of the clean water reservoir and the waste water collection tank is provided on the base unit, and the other is provided on the guide part 6. During use of the machine 2, a user grips a handle 16 provided at the end of the guide part 6 remote from the base unit 6, urges the machine in a forwards or reverse direction across a floor to be cleaned, and steers the machine 2 by tilting the guide part 6, with respect to the base unit 4, in a forwards or backwards and / or side to side direction. Means (not shown) are provided for delivering cleaning liquid from the cleaning liquid reservoir to the floor tool to provide wet cleaning. A suction collector (not shown) is provided for lifting waste liquid from the floor and conveying it to the waste liquid collection tank. The suction collector comprises a floor-facing trailing squeegee collector 18 assembly disposed behind the floor facing treatment tool 8 in a normal forwards direction of cleaning, indicated by arrow F in figure 2. The base unit 4 is connected to the guide part 6 via a joint 20. The joint 20 comprises a flexible member, which enables the guide part 6 to be tilted in a forwards / backwards and side-to-side direction in use of the machine 2. For example, referring to figures 4a and 4b, the guide part 6 may be tilted to a maximum angle 9 away from a vertical orientation V. Figure 4a shows the guide part 6 tilted forwards at an angle 6 to the horizontal orientation V. The guide part 6 can also be tilted backwards, i.e. to the right in the orientation of figure 4a, up to angle 6. Figure 4b shows the guide part 6 tilted to one side, i.e. to the right in the orientation of figure 4b, to angle 6. The guide part 6 can also be tilted to the opposite direction, i.e. to the left in the orientation of figure 4b, up to angle 6. Angle 6 could, for example be 45°. For angle 6 values up to 90°, a cone-shaped range of movement is enabled, i.e. the guide part 6 can be tilted relative the base unit 4 within a cone-shaped locus of movement defined by angle 6. In some embodiments, an angle 6 of 90° could be enabled, providing a hemispherical locus of tilting movement the guide part 6 relative to the base unit 4. Figures 5b and 5c illustrate sequential steps of a handle locking mechanism. Figure 5a is a more detailed view schematic view of a flexible member providing the joint 20, connecting the base part 4 and the guide part 6. The joint 20 is free to flex, thereby to tilt the guide part 6 with respect to the base part 4, forwards and backwards, and side to side, within the full cone-shaped or hemispherical range of movement as discussed above. In this embodiment, the joint 20 is of a stiffness which is sufficiently low that it does not maintain the guide part 4 in an vertical orientation I upright position, i.e. when the guide part 4 is not being held by a user or rested against a wall, the joint 20 will flex and allow the guide part 4 to fall under its own weight. Figures 5b and 5c illustrate a locking mechanism which can be used to maintain the guide part 6 in an upright position, i.e in a substantially vertical orientation, for example when the machine 2 is not in use. The locking mechanism comprises a locking member comprising a rigid collar 30, and a location means comprising a channel 34. Figure 5b shows an unlocked position, wherein the collar 30 is in a raised position, surrounding the guide part 6 at a lower end thereof. The joint 20 is uncovered and is free to flex, thereby to tilt the guide part 4 with respect to the base unit, within the full range of movement. The collar 30 is moveable from the raised position of figure 5b, downwardly towards the base unit 4, (i.e. in the direction of arrow L in figure 5c), to a locked position as shown in figure 5c. The collar 30 is moved downwardly until a lower edge 32 of the collar 30 locates into an aperture I channel 34 provided on a upper surface 44 of the base unit 4. In the locked position, the joint 20 is surrounded by the collar 20, and the collar 20 is rigidly fixed in position with respect to the base unit 4 by the location of the lower edge 32 within the aperture 34. The joint 20 is thereby locked, i.e. flexing of the joint 20 is prevented by the collar 20. The guide part 6 is therefore also locked, i.e. it is prevented from tilting with respect to the base unit 6, and is maintained in an upright position I substantially vertical orientation. As an alternative to providing a locking mechanism, the joint 20 may be configured to return the guide part 6 to a vertical orientation under bias. For example, the material and / or configuration of the joint 20 may be selected to provide a stiffness of the joint 20 which is sufficiently low so as to allow the user to tilt the handle portion 6 away from the vertical orientation when required, yet sufficiently high so as to cause the joint 20 to spring back to a non-flexed configuration, thereby to return the guide part 6 to a vertical position, when user force has been removed. Figure 6a illustrates the joint 20 when a user is applying a force to the guide part 6 (for example via the handle 16, or by pushing directly on the guide part 6), thereby causing the guide part 6 to be tilted away from the vertical orientation V. One side (the left side in the orientation of figure 6a) of the joint 20 experiences a tension force, indicated by arrows T, as it is stretched, and the other side (the right side in the orientation of figure 6a) experiences a compressive force, indicated as arrow C, as it is compressed. The handle portion 6 will maintain this tilted orientation as long as the user is applying sufficient force to the handle portion 6 to overcome a natural biasing I shape memory of the joint 20. When the user stops applying any force to the handle portion 6, the flexible member returns, in the direction of arrow R in figure 6b, to the upright position, i.e. to a vertical orientation, under the natural biasing I shape memory of the joint 20. The handle portion 6 will remain in the upright position until next use, without a requirement for a locking mechanism. Figures 7a onwards disclose example embodiments of the joint 20 of the present invention. Features disclosed in respect of one embodiment may be provided in combination with features of another embodiment. Figures 7a and 7b illustrate a first example embodiment of the joint, indicated generally as 120. For simplicity, only the joint 120 is shown; other parts of the machine are not shown. In this embodiment the joint 120 comprises a solid flexible member comprising a substantially cylindrical flexible section 124. The cylindrical flexible section 124 comprises a core provided by a solid internal shaft 126 formed of a flexible material such as a rubber-like material, and an external sheath 128 formed of a semi-rigid plastic material, which surrounds the internal shaft 126. The internal shaft 126 is visible in the figures through a plurality of slots I cut-outs 130 provided in the external sheath 128. The slots 130 in the external sheath 128 provide a plurality of living hinges 122, i.e. integral hinges / flexure bearings. Locations of the visible living hinges 122 on Figure 7b are each indicated by an X. At an upper end of the joint 120 is provided an upper mount plate 150, and at a lower end of the joint 120 is provided a base mount plate 160. A lower end of the guide part 6 of the machine 2 is fixedly attached to an upper surface 152 of the upper mount plate 150. An underside surface 164 of the base mount plate 160 is fixedly attached to the base unit 4 of the machine 2. The living hinges 122 enable flexing of the cylindrical flexible section 124, allowing a fore / aft and a side-to-side movement of the guide part 6, whilst preventing any rotational I twisting movement of the flexible section 124, therefore enabling transmission of torque from the guide part 6 to the base unit 4 during use of the machine 2. The slots 130 are provided on the external sheath 128 in a consistent manner, i.e. in a uniform pattern, to enable consistent flexing across the flexible section 124. Tilting of the guide part 6 with respect to the base unit 4 is thereby enabled by the flexible section 124 of the joint 120. The guide part 6 may be tilted with respect to the base unit 4, for example by up to 90° from a vertical direction. Figures 8a to 8c illustrate a second embodiment of the joint, indicated generally as 220. For simplicity, only the joint 220 is shown; other parts of the machine are not shown. In this embodiment, the joint 220 comprises a solid flexible member comprising a cylindrical flexible section 224. The cylindrical flexible section 224 comprises a core provided by a solid shaft 240 formed of a flexible material such as a rubber-like material, which is overmoulded onto a high-strength internal spring 242 so as to enclose the internal spring 242 within the shaft 240. In figures 8a and 8b, the shaft 240 is illustrated as partially transparent so as to illustrate the spring 242. At an upper end of the joint 220 is provided an upper mount plate 250, and at a lower end of the joint 220 is provided a base mount plate 260. A lower end of the guide part 6 of the machine 2 is fixedly attached to an upper surface 252 of the upper mount plate 250. An underside surface 164 of the base mount plate 260 is fixedly attached to the base unit 4 of the machine 2. The shaft 240 and the internal spring 242 extend between an underside surface 254 of the upper mount plate 250, and an upper surface 262 of the base mount plate 260. The shaft 240 and the internal spring 242 enable flexing of the cylindrical flexible section 224, allowing a fore / aft and a side-to-side movement of the guide part 6, whilst preventing any rotational I twisting movement of the flexible section 224, therefore enabling transmission of torque from the guide part 6 to the base unit 4 during use of the machine 2. Tilting of the guide part 6 with respect to the base unit 4 is thereby enabled by the flexible section 224 of the joint 220. The guide part 6 may be tilted with respect to the base unit 4, for example by up to 90° from a vertical direction. Figures 9a to 9c illustrate a third embodiment of the joint, indicated generally as 320. For simplicity, only the joint 320 is shown; other parts of the machine are not shown. At an upper end of the joint 320 is provided an upper mount plate 350, and at a lower end of the joint 320 is provided a base mount plate 360. A lower end of the guide part 6 of the machine 2 is fixedly attached to an upper surface 352 of the upper mount plate 350. An underside surface 364 of the base mount plate 360 is fixedly attached to the base unit 4 of the machine 2. In this embodiment, the joint 320 comprises a solid flexible member comprising a substantially cylindrical section 324. The substantially cylindrical section 324 comprises a core provided by an internal solid flexible member 340 (visible on the cross-sectional view of figure 9c), surrounded by an external sheath comprising a plurality of interlocked segments 346. Each of the segments 346 is provided with a plurality of alternating teeth and recesses, wherein the teeth of one segment 326 interlock into the recesses of an adjacent (i.e. above / below) segment 346. The plurality of segments 346 includes an uppermost segment 346a, a lowermost segment 346c, and one or more intermediate segments 346b. The uppermost segment 346a is adjacent to, and mechanically fixed to, an underside surface 354 the upper mount plate 350, and the lowermost segment 346c is adjacent to, and mechanically fixed to, an upper surface 362 the base mount plate 360. The intermediate segments 346c are stacked vertically above each other between the uppermost segment 346a and the lowermost segment 346b, and are maintained in position vertically by the uppermost segment 346a and the upper mount plate 350, and by the lowermost segment 346b and the base mount plate 360. The intermediate segments 346b are otherwise "floating", i.e. they not mechanically joined to one another, or to any other part of the joint 320. This allows the joint 320 to flex, enabling a fore / aft and a side-to-side movement of the guide member 6, as the intermediate segments 346b are able to separate to cope with stretching I flexing of the flexible member 324. When torque is applied, at least one side of the teeth of the segment 346 will always be interlocked with an adjacent segment 346, therefore, allowing transmission of torque from the guide part to the base. The internal flexible member 340 and the external floating segments 346 enable flexing of the cylindrical flexible section 124, allowing a fore / aft and a side-to-side movement of the guide part 6, whilst preventing any rotational I twisting movement of the flexible section 324, therefore enabling transmission of torque from the guide part 6 to the base unit 4 during use of the machine 2. Tilting of the guide part 6 with respect to the base unit 4 is thereby enabled by the flexible section 324 of the joint 320. The guide part 6 may be tilted with respect to the base unit 4, for example by up to 90° from a vertical direction. Tilting of the guide part 6 with respect to the base unit 4 is thereby enabled by the flexible section of the joint 320. The guide part 6 may be tilted with respect to the base unit 4, for example by up to 90° from a vertical direction. Figures 10a to 10e illustrate a fourth embodiment of the joint, indicated as 420. For simplicity, only the joint 420 is shown; other parts of the machine are not shown. In this embodiment, the joint 420 comprises a solid flexible member comprising a substantially cylindrical flexible section 424. The cylindrical flexible section 424 comprises a hose 448, which is tightly wound around a core, provided by an internal, solid cylindrical rod / shaft 440 (visible on the cross-sectional view of figure 10c), formed of a flexible material such as a rubber-like material. At an upper end of the joint 420 is provided an upper mount plate 450, and at a lower end of the joint 420 is provided a base mount plate 460. A lower end of the guide part 6 of the machine 2 is fixedly attached to an upper surface 452 of the upper mount plate 450. An underside surface 164 of the base mount plate 460 is fixedly attached to the base unit 4 of the machine 2. The hose 448 and the internal cylindrical shaft 440 extend between an underside surface 454 of the upper mount plate 450, and an upper surface 464 of the base mount plate 460. The hose 448 of figures 10a to 10c has a spiral external profile 470, and a smooth internal profile 472. The alternative of hoses 448', 448" of figures 10d and 10e both have a corrugated external profile 470', 470". Figure 10f is a schematic representation of corrugated profile. The internal and external profiles of other alternative embodiments of hoses could be spiral, corrugated, or smooth, or a combination thereof. The hose 448 may be formed of a plastic; for example the hose 448 could be moulded in a PA6 plastic. Walls of the hose 448 could be reinforced by embedded metal or engineering plastic reinforcement. When the hose 448 is arranged around the internal cylindrical shaft 440 and torque is applied to the joint 420, the hose 448 prevents any twisting I rotation of the cylindrical flexible section 424. The hose 448 and the cylindrical shaft 440 therefore enable flexing of the cylindrical flexible section 424, allowing a fore / aft and a side-to-side movement of the guide part 6, whilst preventing any rotational I twisting movement of the flexible section 424, therefore enabling near instant transmission of torque with minimal lag from the guide part 6 to the base unit 4 during use of the machine 2. Without the internal cylindrical shaft 440, the hose 448 would be susceptible to impact damage. During bending the cylindrical shaft 440 prevents the hose 448 from kinking by providing internal support. Tilting of the guide part 6 with respect to the base unit 4 is thereby enabled by the flexible section of the joint 420. The guide part 6 may be tilted with respect to the base unit 4, for example by up to 90° from a vertical direction. The invention is set our out in the following numbered paragraphs: 1. A hand-guided floor treatment machine comprising a base unit which carries at least one motor-driven floor-facing treatment tool, and an elongate guide part which has an upper end region provided with a handle for guiding the machine in a working direction; wherein the base unit is connected to the guide part via a joint, the joint comprising a flexible member comprising a solid flexible core, wherein flexing of the flexible member enables the guide part to be tilted relative to the base unit in a fore and aft, and a side to side direction. 2. A machine as recited in paragraph 1 wherein the joint comprises an upper mount plate attached to a lower end region of the guide part, and a base mount attached to the base unit, and wherein the flexible member extends between the upper mount plate and the base mount plate. 3. A machine as recited in paragraph 1 or paragraph 2 wherein the flexible member comprises a rubber or a rubber-like material. 4. A machine as recited in any one of the preceding paragraphs wherein the core comprises a cylindrical shaft. 5. A machine as recited in paragraph 4 wherein a spring is encased within the core. 6. A machine as recited in paragraph 4 or paragraph 5 wherein the core is surrounded by an external sheath. 7. A machine as recited in paragraph 6 wherein in the external sheath is formed of a semi-rigid material, wherein a plurality of slots provided in the external sheath provide a plurality of living hinges allowing flexing of the flexible member. 8. A machine as recited in paragraph 7 wherein the slots are provided on the external sheath a uniform pattern. 9. A machine as recited in paragraph 6 in the external sheath comprises a plurality of interlocked segments. 10. A machine as recited in paragraphs 2 and 9 wherein the plurality of interlocked segments comprises an uppermost segment rigidly attached to an underside surface of the upper mount plate, and a lowermost segment rigidly attached to an upper surface of the base mount plate, and a plurality of intermediate segments located between the uppermost segment and the lowermost segment. 11 . A machine as recited in paragraph 4 wherein the cylindrical shaft is surrounded by a hose. 12. A machine as recited in paragraph 11 wherein the hose has a smooth, spiral, or corrugated external profile. 13. A machine as recited in paragraph 11 or paragraph 12 wherein the hose has a smooth, spiral, or corrugated internal profile. 14. A machine as recited in any one of paragraphs 11 to 13 wherein walls of the hose are reinforced by embedded metal or engineering plastic reinforcement. 15. A machine as recited in any one of the preceding paragraphs, wherein flexing of the flexible member enables the guide part to be tilted with respect to the guide part within a cone-shaped or hemispherical locus of movement. 16. A machine as recited in any one of the preceding paragraphs, wherein the joint is configured to return the guide part to a vertical orientation under bias. 17. A machine as recited in any one of the preceding paragraphs, further comprising a locking mechanism comprising a locking member, movable between an unlocked position in which tilting of the guide part relative to the base unit is enabled, and a locked position in which tilting of the guide part relative to the base unit is prevented. 18. A machine as recited in paragraph 17 wherein the locking member comprises a rigid collar, which in the unlocked position, is raised relative to the base unit and surrounds a lower end of the guide part, and which is lowerable towards the base unit thereby to move to the locked position in which the collar surrounds the joint. 19. A machine as recited in paragraph 18 wherein the locking mechanism further comprises a locating means comprising a channel which receives a lower edge of the collar in the locked position. 20. A machine as recited in any one of the preceding paragraphs comprising a floor scrubber drier.

Claims

1. A hand-guided floor treatment machine comprising a base unit which carries at least one motor-driven floor-facing treatment tool, and an elongate guide part which has an upper end region provided with a handle for guiding the machine in a working direction;wherein the base unit is connected to the guide part via a joint, the joint comprising a flexible member comprising a solid flexible core and wherein a spring is encased within the core, wherein flexing of the flexible member enables the guide part to be tilted relative to the base unit in a fore and aft, and a side to side direction.

2. A machine as claimed in claim 1 wherein the joint comprises an upper mount plate attached to a lower end region of the guide part, and a base mount attached to the base unit, and wherein the flexible member extends between the upper mount plate and the base mount plate.

3. A machine as claimed in claim 2 wherein the spring extends between an underside of the upper mount plate, and an upper surface of the base mount plate.

4. A machine as claimed in any one of the preceding claims wherein the spring comprises a high strength spring.

5. A machine as claimed in any one of the preceding claims wherein the flexible member comprises a rubber or a rubber-like material.

6. A machine as claimed in any one of the preceding claims wherein the core comprises a cylindrical shaft.

7. A machine as claimed in claim 6 wherein the core is surrounded by an external sheath.

8. A machine as claimed 7 wherein in the external sheath is formed of a semirigid material, wherein a plurality of slots provided in the external sheath provide a plurality of living hinges allowing flexing of the flexible member.

9. A machine as claimed in claim 8 wherein the slots are provided on the external sheath a uniform pattern.

10. A machine as claimed in claim 7 in the external sheath comprises a plurality of interlocked segments.

11. A machine as claimed in claim 6 wherein the cylindrical shaft is surrounded by a hose.

12. A machine as claimed in claim 11 wherein the hose has a smooth, spiral, or corrugated external profile and / or internal profile.

13. A machine as claimed in claim 11 or claim 12 wherein walls of the hose are reinforced by embedded metal or engineering plastic reinforcement.

14. A machine as claimed in any one of the preceding claims, wherein flexing of the flexible member enables the guide part to be tilted with respect to the guide part within a cone-shaped or hemispherical locus of movement.

15. A machine as claimed in any one of the preceding claims, wherein the joint is configured to return the guide part to a vertical orientation under bias.

16. A machine as claimed in any one of the preceding claims comprising a floor scrubber drier.

17. A method of forming the joint a machine as claimed in claim 1, comprising overmoulding a flexible material onto the spring.

18. A method as claimed in claim 17 further comprising providing an upper mount plate at an upper end of the joint, and providing a base mount plate at a lower end of the joint.

19. A method as claimed in claim 18, further comprising fixedly attaching a lower end of the guide part of the machine to an upper surface of the upper mount plate.

20. A method as claimed in claim 18 or claim 19, further comprising fixedly attaching an underside surface of the base mount plate to the base unit of the machine.T +44(0)30 0300 2000A

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