Floor treatment machine

Abstract

The present invention relates to the field of floor treatment machines for scrubbing, polishing, sanding or burnishing floors. In these machines one or more driven rotatable work heads (such as scrubbing brushes) are provided for agitating the floor surface. There is provided a walk-behind floor treatment machine comprising: a base portion provided with and supported by at least one rotatable work head for treating the floor, a handle portion for steering or guiding the machine along a working direction of travel and adapted to be pivotable with respect to the base portion, drive means for rotating the work head with respect to the base portion, floor-engaging wheel means for supporting the handle portion, the wheel means having a substantially transverse axis of rotation so as to permit travel in the working direction, the wheel means being coupled to the base portion by a linkage which permits vertical travel of the base portion and associated work head or heads with respect to the wheel means, but which provides transverse constraint to limit or prevent yawing of the base portion with respect to the wheel means, wherein a lower region of the handle portion is pivotably connected to the wheel means via an articulated joint, the arrangement being such that the handle portion may be manipulated to act on the wheel means so as to yaw steer the wheel means about a yaw axis defined by the floor-engaging contact of the wheel means, the yawing of the wheel means causing the base portion to yaw in response to yaw steering, and wherein a handle pivot lock mechanism is provided in which the adoption of a predetermined handle portion orientation permits one or more locking feature to act on one or more corresponding constraint feature so as to prevent pivoting movement of the handle portion with respect to the base portion. The predetermined handle orientation may be a vertical orientation. In the predetermined orientation the locking feature becomes aligned with the constraint feature so as to permit mutual engagement, and when the orientation is not achieved misalignment prevents engagement of the features.

1 . A walk-behind floor treatment machine comprising:
 a base portion provided with and supported by at least one rotatable work head for treating the floor,   a handle portion for steering or guiding the machine along a working direction of travel and adapted to be pivotable with respect to the base portion,   drive means for rotating the work head with respect to the base portion,   floor-engaging wheel means for supporting the handle portion, the wheel means having a substantially transverse axis of rotation so as to permit travel in the working direction, the wheel means being coupled to the base portion by a linkage which permits vertical travel of the base portion and associated work head or heads with respect to the wheel means, but which provides transverse constraint to limit or prevent yawing of the base portion with respect to the wheel means,   wherein a lower region of the handle portion is pivotably connected to the wheel means via an articulated joint, the arrangement being such that the handle portion may be manipulated to act on the wheel means so as to yaw steer the wheel means about a yaw axis defined by the floor-engaging contact of the wheel means, the yawing of the wheel means causing the base portion to yaw in response to yaw steering, and   wherein a handle pivot lock mechanism is provided in which the adoption of a predetermined handle portion orientation permits one or more locking feature to act on one or more corresponding constraint feature so as to prevent pivoting movement of the handle portion with respect to the base portion.   
     
     
         2 . A floor treatment machine as claimed in  claim 1  wherein the predetermined handle orientation is a vertical orientation. 
     
     
         3 . A floor treatment machine as claimed in  claim 1  or  claim 2  wherein in the predetermined orientation the locking feature becomes aligned with the constraint feature so as to permit mutual engagement, and when the orientation is not achieved misalignment prevents engagement of the features. 
     
     
         4 . A floor treatment machine as claimed in any of the preceding claims wherein the locking feature or features are one or more detent feature and the constraint feature or features are one or more indent feature, one of said features being associated with the base portion or linkage and the other of said features being associated with the handle portion. 
     
     
         5 . A floor treatment machine as claimed in any of the preceding claims wherein the pivoting of the handle is up/down pivoting about a transverse axis, and the features act to secure the handle portion against pivoting with respect to the transverse axis. 
     
     
         6 . A floor treatment machine as claimed in any of the preceding claims wherein the wheel means comprises a wheel, roller or ball, preferably a single wheel, roller or ball, disposed at a lower region of the handle portion. 
     
     
         7 . A floor treatment machine as claimed in any of the preceding claims wherein the wheel means has a fixed transverse axis of rotation. 
     
     
         8 . A floor treatment machine as claimed in any preceding claim wherein the linkage comprises at least one strut, one end region of which is provided with a pitch pivotal connection to the wheel means, which connection is coaxial with the wheel means axis of rotation, and wherein an other end region of the strut is attached to the base portion. 
     
     
         9 . A floor treatment machine as claimed in  claim 8  wherein the or each strut is provided with a convex upper surface provided with the indent feature, and the detent feature is connected to a lower region of the handle portion for travel in an arc which corresponds to the profile of the convex upper surface, the arrangement being such that the detent feature can slide over the convex surface during up/down pivoting of the handle portion about the transverse axis. 
     
     
         10 . A floor treatment machine as claimed in  claim 9  wherein a lock actuator urges the detent feature against the surface so when the detent feature and indent feature are aligned the detent feature projects into the indent so as to lock motion of the handle portion. 
     
     
         11 . A floor treatment machine as claimed in any of  claims 8  to  10  wherein there are two said struts disposed on either side of the wheel means in a generally parallel arrangement and two respective detent features, one for each strut. 
     
     
         12 . A floor treatment machine as claimed in  claim 11  wherein the two detent features are provided by respective downwardly extending prongs of a locking member fork. 
     
     
         13 . A floor treatment machine as claimed in any of  claims 9  to  12  wherein the convex surface is provided with end stops at opposite ends thereof, which end stops limit travel of the detent along the convex strut profile so as to limit transverse pivoting of the handle portion to upper and lower arc boundaries. 
     
     
         14 . A floor treatment machine as claimed in any of  claims 8  to  13  wherein the other end region of the strut is attached to the base portion via a pitch pivotal connection. 
     
     
         15 . A floor treatment machine as claimed in  claim 14  wherein said pitch pivotal connections permit the vertical travel of the base portion with respect to the wheel means. 
     
     
         16 . A floor treatment machine as claimed in any of the preceding claims wherein said one or more rotatable work head supports the base portion on the floor surface with the linkage permitting floating vertical travel of the work heads with respect to the wheel means. 
     
     
         17 . A floor treatment machine as claimed in any preceding claim wherein the articulated joint permits side-to-side pivoting of the handle about the joint about an axis perpendicular to the pivot transverse axis. 
     
     
         18 . A floor treatment machine as claimed in any of the preceding claims wherein the side-to-side pivot of the articulated joint is provided at a location vertically spaced apart and above the transverse pivot. 
     
     
         19 . A floor treatment machine as claimed in  claim 17  or  claim 18  wherein a side-to-side pivot locking mechanism is provided in which entry of a traveller associated with the handle portion into a constraint feature prevents side-to-side pivoting. 
     
     
         20 . A floor treatment machine as claimed in  claim 19  wherein the traveller is a retractable shuttle accommodated in a lower end region of the handle portion, the shuttle being movable from a retracted position in which side to side pivoting of the handle portion is permitted, and an extended position in which a distal end of the shuttle is constrained between cheek features which prevent pivoting from side-to-side of the handle portion. 
     
     
         21 . A floor treatment machine as claimed in  claim 20  wherein the cheek features define a generally vertical enclosure for accommodating the distal end of the shuttle, the shuttle traveling axially with respect to the handle portion, so that when the shuttle distal end is constrained the handle is dead centre of the side-to-side handle movement range, which cheek features may be inside faces of the locking member fork. 
     
     
         22 . A floor treatment machine as claimed in any of  claims 12  to  21  wherein the traveller is capable of acting on said locking member fork to cause locking of transverse handle portion pivoting as the side-to-side pivoting is locked. 
     
     
         23 . A floor treatment machine as claimed in  claim 22  wherein the locking member fork and traveller are connected by a pin and track engagement which provides vertical pin constraint and limited lateral pin freedom corresponding to side-to-side handle portion pivoting. 
     
     
         24 . A floor treatment machine as claimed in  claim 23  wherein movement of the traveller towards the constraint condition cause the pin to act on the track wall, and wherein the track is provided in the locking member fork, so that movement of the traveller causes movement of the fork into indent engagement. 
     
     
         25 . A floor treatment machine as claimed in any of  claims 19  to  24  wherein the traveller or shuttle is resiliently biased so that when actuated the traveller/shuttle is urged towards its constraint position. 
     
     
         26 . A floor treatment machine as claimed in any of the preceding claims wherein a distal end of the handle portion is provided with a transversely oriented handle bar for the user to grip with a hand on each side of the bar. 
     
     
         27 . A floor treatment machine as claimed in any preceding claim wherein an upper end region of the handle portion is provided with a handle position locking mechanism actuator.