A MACHINE FOR TREATING FLOOR SURFACES

Abstract: The invention relates to a floor-surface treating machine (1) comprising a chassis (2), on which at least three wheels (4, 5, 6) are mounted, these wheels bearing against the floor surface (3) and being capable of rolling therealong. In each case one (4) of the wheels is driven by drive means, so as to enable the machine to be moved over the floor surface (3), and one (4) of the wheels is steerable so as to enable the machine (1) to be steered along a path adapted for the displacement of a number of rotatable floor-treating devices (7, 8, 9). When seen in a straight movement direction (F), the driving and steering wheel (4) is the centermost wheel, whereas one wheel (5) mounted on one side of the machine is fixed and rotates in the direction of machine movement, and a wheel (6) mounted on the other side of the machine is pivotably mounted.

Description: TITLE OF THE INVENTION: A machine for treating floor surfaces. TECHNICAL FIELD 5 . • The present invention relates to a machine intended for treating floor surfaces, and in particular to one such machine which comprises a frame or a chassis to which there are attached at least three wheels which rest on the floor surface and can roll thereon, of which wheels 0 at least one is driven by drive means, so as to enable the machine to moved over the floor surface by means of the wheels, and of which wheels at least one is steer- able so as to enable the machine to be moved along a path adapted for the displacement of a number of rotat- 5 able floor-treating devices. By "moving" the machine is meant in the following that the machine can be moved by the wheels over a floor surface without carrying out a working function. 0 By "displacement" is meant that the machine is moved over a floor surface on its wheels while performing a floor-treating function, by the action of rotatable devices on said floor surface. 5 BACKGROUND PRIOR ART Various different types of floor-treating machines are known to the art, these machines being adapted to the floor-treatment function concerned, i.e. floor-washing, 0 floor-polishing or floor-rubbing-down functions. It is known to dimension the machines to suit different working conditions, such as the conditions of smaller office premises, large office premises, warehouses, 5 stores etc., and consequently such machines are retailed in various sizes, ranging from large, driven machines to hand-manouvered small machines. It is also known to operate such machines with the aid of robotic devices. These machines are normally of a larger size. The present invention can be considered to relate to a driveable machine. The machine operator sits on the machine and guides said machine over the surface of a floor, although, as will be understood, the machine may also be remotely controlled, either by an operator who walks on one side of the machine, or via a robot-con¬ trolled system. Earlier known driveable machines are intended primarily to perform a floor-sweeping function and to this end are fitted with horizontal, rotatable cylindrical brushes operative to brush large surface effectively, and the machine will also incorporate suction devices whereby particle collections swept by the brushes are removed from the floor by suction. SUMMARY OF THE INVENTION TECHNICAL PROBLEMS When considering the present standpoint of techniques, as described in the aforegoing, it will be seen that a technical problem resides in the provision of a machine intended for treating floor surfaces, primarily a machine for sweeping large floor surfaces which is so constructed as to enable the machine to be guided easily along a desired path by one single wheel, and which is also constructed to be able to displace a number of rotatable brush-units or brushes intended for treating the surface of a floor, preferably, although not exclu- sively, brush units having cylindrical surfaces. It will also be seen that a technical problem resides in the provision of a driveable machine which not only solves the aforesaid technical problem but which also provides the possibility of turning easily round right- angled corners and therewith afford a manouverability . for given applications which is superior to the manouv¬ erability of earlier known constructions. It will also be seen that a technical problem resides in orientating the wheels in relation to the rotatable brush units so that the machine function around an outwardly jutting corner can be effected by displacement in one single direction, and a stationary or insignifi¬ cant movement, while steering around the corner. It will also be seen that a technical problem resides in realizing that the stability and steerability of such machines will be greatly improved when the machine utilizes three wheels which support against a floor surface and are capable of being rolled therealong, and in permitting the center ost wheel to have a steering function as well as a driving function, while mounting a wheel on one side of the machine, the outer side there¬ of, in fixed relationship with respect to its direction and for rectilinear movement, and mounting a pivotable wheel on the other side of the machine. It will also be seen that a technical problem is one of realizing that the ability to swing the machine around an outwardly jutting corner can be improved when the fixed wheel is positioned at a further distance from the centermost wheel than the pivotable wheel. A still more qualified technical problem to be solved is one of realizing that to enable the machine to sweep around an outwardly jutting corner, it is necessary for the fixed wheel to be located at twice, or substantially twice the distance in relation to the pivotable wheel, and that at least one rotatable brush unit should be located between the fixed wheel and the pivotable wheel, and in the vicinity of said pivotable wheel. For the purpose of creating stability in balance of a large driveable machine, while using three rollable wheels, it will be seen that a technical problem is one of realizing that a cylindrical and rotatable brush-unit mounted between the fixed and the pivotable wheel and positioned substantially at right angles to the direc¬ tion of machine movement is able to function as an additional support should the machine come out of bal- ance. It will also be seen that a technical problem is one of realizing that machine stability can be further improved by providing brush units in front of the fixed wheel, suitably two rotatable brush units, in the form of cylindrical brush units, said brush units further assisting in stabilizing movement and displacement of the machine. It will also be seen that a technical problem associated with a machine successful in solving a number of the aforesaid technical problems is one of providing a suitable location for the necessary batteries and driv¬ ing seat, not only with respect to machine stability and the ease with which the machine can be swung, but also with respect to the ease with which the operator sitting on the machine is able to anouver said machine. SOLUTION The object of the present invention is to provide a floor-surface treating machine which solves one or more of the aforesaid technical problems and which comprises a frame or chassis having mounted thereon at least three wheels which bear against the floor surface and are capable of rolling therealong, of which wheels at least one is driven by drive means so as to enable the machine to be displaced or moved along a floor surface by means of said wheels, and at least one wheel is steerable so as to enable the machine to be displaced or moved along a path adapted to enable a number of rotatable, floor- surface treatment means to be displaced along said path. It is proposed in accordance with the invention that when seen in the direction of forward movement the centermost wheel of the machine will be a driving and steering wheel, and that one wheel mounted on one side of the machine will be fixed in relation to said chassis and directed for movement of the machine in a straight line, either forwards or backwards, and that a wheel mounted on the other side of the machine is freely pivotable about a vertical axis. It also lies within the scope of the invention, for embodiments at present proposed, for the centermost wheel to constitute the rearmost wheel of the machine, as seen in the direction of forward movement of the machine. The fixed wheel is preferably located at a further distance from the centermost wheel than the pivotable wheel. It is also proposed that the fixed wheel is located at twice or substantially twice the distance from the centermost wheel than the pivotable wheel, with space for accommodating a rotatable device being provid¬ ed between the fixed and the pivotable wheel. The rotat- able device shall be positioned adjacent the pivotable wheel. It is also proposed that a rotatable brush unit is mounted between the fixed and the pivotable wheel, and that the rotational axis of the brush unit is located horizontally and at right angles to a rectilinear direc- tion of movement. Mounted in front of the fixed wheel, as seen in the forward direction of the machine, are two rotatable brushes, the rotational axes of which are also posi- tioned horizontally and at right angles to a rectilinear movement direction. The driving and steering centermost wheel can be rotated through 360°. In accordance with one embodiment of the invention, the necessary batteries are placed in a chassis space be¬ tween the centermost wheel and the pivotable wheel, whereas the driver's seat is positioned adjacent to and above the pivotable wheel. Finally, the chassis preferably has a frame attached thereto, for carrying said two rotatable brushes. ADVANTAGES Those advantages primarily afforded by the driveable, floor-sweeping machine in accordance with the present invention reside in the ability to displace and move the machine with the aid of three wheels, of which one is a driving and a steering wheel, one is fixedly mounted in a direction conforming to normal rectilinear movement of the machine, whereas the third wheel is freely pivotal. Thus, there is provided a machine which can be readily displaced along different paths and which enables, to particular benefit, the machine to sweep around angled. outwardly jutting corners without needing to reverse the machine. The invention also enables batteries, driver seat and other equipment on the chassis to be arranged in a manner such as to impart stability to the machine. The primary characteristic features of an inventive machine are set forth in the characterizing clause of the following Claim 1. BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of a floor-sweeping machine incorporating characteristic features significant of the present invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 is a perspective view illustrating the basic features of the machine, and shows for illustrative purposes, machine parts which would normally be hidden from view, and Figure 2 is a perspective view of a suitable frame construction capable of supporting three wheels and a rotatable, cylindrical brush- unit in accordance with the principles of the invention. DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED Figure 1 illustrates in perspective an embodiment of a floor-surface treating machine, particularly a floor- sweeping machine 1. The machine 1 comprises a forward frame or chassis 2 which carries three wheels 4, 5, 6 which bear against a floor surface 3 and which can roll on said floor sur- face. One of the wheels, 4, is driven by drive means not shown, so as to enable the machine 1 to be displaced along the floor surface 3, by means of said drive means and said wheel 4. The machine 1 can be driven by said drive means in two mutually opposite directions, although it is assumed in the following that the direction indicated by the arrow "F" is the direction of forward movement of said ma- chine. In order to facilitate an understanding of the signifi¬ cant characteristics of the invention, the machine 1 is also allotted a longitudinal direction or a longitudi- nally extending plane "A". In the illustrated embodiment, the rotatable, sweeping devices have the form of cylindrical brush-units with a horizontal rotational axis, although the inventive principles can also be applied to rotatable brush-units which have vertical axes of rotation. One of the wheels, namely the wheel 4, is a steerable wheel and is steered by known"means 4a, so as to enable the machine 1 to be displaced and moved along a prede¬ termined path, essentially any desired path, adapted for enabling a number of rotatable floor-treating devices or brush-units 7, 8, 9 to work along parts of adjacent walls and around corners. Each of the brush-units comprises a cylindrical brush- unit. The brush-units are rotatably mounted on respec¬ tive, mutually parallel axles 7a, 8a and 9a respective¬ ly. When the machine is driven straight ahead, the rearmost wheel, or centermost wheel 4 is both driving and steer¬ ing, whereas the wheel mounted on the left side of the machine is fixed and rotates in the direction of said direction of forward movement or parallel with the left chassis-part 21 of the chassis 20. The wheel 6 mounted on the other side of the machine 1, on the right side of said machine as seen in the direc¬ tion of forward movement thereof, is pivotally mounted to the right chassis-part 22 of said chassis. The distance of the fixed wheel 5 from the centermost wheel 4 shall be greater than the distance of the pivot¬ able wheel 6 from said centermost wheel, and it is preferred that the distance of said fixed wheel 5 from said centermost wheel is twice or essentially twice the distance of the pivotable wheel 6 from said centermost wheel. Mounted between the fixed wheel 5 and the pivotable wheel 6 is a rotatable brush-unit 7 of the aforemen¬ tioned kind. The rotational axle of the brush-unit extends horizon- tally and at right angles to the direction of forward movement of the machine, or to the plane "A". Mounted adjacent to the fixed wheel 5 and forwardly of said wheel as seen in the direction of movement "F" are two further rotatable brush-units 8,9, the rotational axles of which also extend horizontally and at right angles to the direction of forward movement or to the plane "A". The driving and steering wheel 4 can be rotated through 360°, in a known manner, and .is driven by an electric motor, a d.c. motor, not shown. The batteries 10 required for powering the machine rest on the chassis or frame in the space between the center- most wheel 4 and the pivotable wheel 6, whereas the driver's seat 11 is positioned adjacent to and above the pivotal wheel 6. A frame 12 is attached to the chassis 2 and carries, inter alia, the two rotatable brush-units 8, 9 before- mentioned. In the direction of forward, or rectilinear, movement of the machine, the wheels 4, 5 and 6 are orientated in or parallel with the plane "A", as illustrated in Figure 1. The brush-units 7, 8 and 9 can be orientated so as to be able to brush and sweep up against a wall-part as the machine is displaced therealong. It will be understood that when the machine illustrated in Figure 1 is to sweep around an outwardly jutting corner, and not only a corner whose angle is smaller than 90 * but also a corner whose angle is greater than 90 * , the brush-units 8,9 will brush along a wall-part up to the location of said corner and somewhat therebeyond, until the corner is located at the point 13 shown in Figure l. This point 13 is located immediately opposite the wheel 5 and perpendicularly to the plane "A". When the corner is located in this position relative to the machine 1, the wheel 4 is swivelled at right angles to the plane "A", as illustrated in Figure 2, and steers the machine away from said wall-part, which means that the fixed wheel 5 will describe a circular movement around the corner to an extent determined by the angle of said corner. The wheel 6 is, at the same time, swi¬ velled to a position corresponding to the position of the driving and steering wheel 4. Consequently, the brush-unit 7 will move away from the wall-part while the brush-units 8 and 9 approach adja¬ cent wall-parts. When the brush-units 8 and 9 are located in the vicinity of mutually adjacent wall-parts, a forwardly-directed movement along said adjacent wall-parts is activated. The brush-unit 7 will then begin to brush some distance away from the corner, in a direction towards said corner and then along an adjacent wall-part. It will be understood that the invention is "not restricted to the illustrated and described embodiments thereof and that modifications can be made within the scope of the following claims.

Claims: CLAIMS 1. A machine (1) intended for treating a floor surface (3) and comprising a chassis (2) which has rotatably mounted thereon at least three wheels (4, 5, 6) which rest against said floor surface and which are capable of rolling therealong, of which wheels one (4) is driven by drive means so as to enable the machine to be moved over the floor surface (3) on said wheels, and of which wheels one is steerable (4) to enable said machine to be moved along a path adapted for displacement of a number of rotatable device (7, 8, 9) operative to work said floor surface, c h a r a c t e r i z e d in that when seen in the direction of forward movement of the machine the centermost wheel (4) is a driving and steering wheel, one wheel (5) located on one side of the machine is fixed and rotates in the direction of machine move¬ ment, and one wheel (6) is pivotally mounted on the other side of said machine. 2. A machine according to Claim 1, c h a r a c ¬ t e r i z e d in that the centermost wheel (4) is normally the rearmost wheel. 3. A machine according to Claim l or 2, c h a r a c ¬ t e r i z e d in that the distance of the fixed wheel (5) from the centermost wheel (4) is greater than the distance of the pivotable wheel (6) from said centermost wheel. 4. A machine according to Claim 3, c h a r a c ¬ t e r i z e d in that the distance of the fixed wheel (5) from the centermost wheel is twice or substantially twice the distance in relation to the pivotable wheel. 5. A machine according to Claim 1, c h a r a c ¬ t e r i z e d in that a rotatable brush (7) is mounted between the fixed wheel (5) and the pivotable wheel (4). 6. A machine according to Claim 5, c h a r a c ¬ t e r i z e d in that a rotational axle (7a) extends horizontally and perpendicularly to movement of the machine in a straight line. 7. A machine according to Claim 5, c h a r a c ¬ t e r i z e d in that two further rotatable brushes (7, 9) are mounted in front of the fixed wheel (5). 8. A machine according to Claim 7, c h a r a c - t e r i z e d in that the rotational axles (8a, 9a) extend horizontally and perpendicularly to movement of the machine in a straight line. 9. A machine according to Claim 1, σ h a r a c - t e r i z e d in that the driving and steering wheel (4) can be rotated through 360 * . 10. A machine according to Claim 1, c h a r a c ¬ t e r i z e d in that the requisite batteries (10) are positioned between the centermost wheel (4) and the pivotable wheel (6). 11. A machine according to Claim 1 or 10, c h a r a c ¬ t e r i z e d in that a driver's facility (11) is positioned adjacent to and above the pivotable wheel (6). 12. A machine according to Claim 7 or 8, c h a r a c ¬ t e r i z e d in that a frame (12) is attached to the chassis (21) and is intended to carry said two further rotatable brushes (8, 9).

Inventors: LILJA BO VILHELM, LILJA, BO, VILHELM
Applicants: LILJA BO VILHELM, LILJA, BO, VILHELM
Application year: 1990
Main classification: A47L41
IPC codes: A47L11