Transparent and translucent materials such as glass and Perspex etc are increasingly being used in modern present day buildings. Frequently these materials are used in high windows, and present cleaning difficulties, particularly where the glass etc forms part of a roof of a building, and cannot safely bear the weight of a person to clean the exterior surface of the glass panels.

According to the present invention there is provided apparatus for cleaning the surface of a building comprising a wiper and a driving means to move the wiper across the surface of the building.

The apparatus is preferably disposed against the outer surface of the building, but can equally be disposed against the inner surface so that the wiper can wipe the inner and/or outer surface of the building.

The wiper is preferably of resilient material such as rubber, and conventional designs of rubber wiper blade are suitable.

The driving means can comprise a belt and cog or wheel system wherein at least one end of the wiper is attached to the belt, and the belt is moved between two or more cogs. Preferably the movement of the wiper follows a straight line and ideally the wiper is moved between the top and the bottom of the surface being cleaned. Alternatively, the wiper can be moved from one side to the other. In such embodiments, the wiper can be carried on tracks guiding the path of the wiper.

In the case where the wiper moves between the top and the bottom of the surface then the tracks can be arranged on either side of the surface. The tracks can optionally contain or otherwise incorporate the drive means or a portion thereof. Typically, the tracks can cover the drive means so as to improve the aesthetic appearance of the outside surface of the building.

The tracks can be generally parallel to the surface of the building, but at one or more points (e. g. at one end) at least one can typically extend outwards from the plane of the surface being wiped at an angle of 5°-80° preferably 15-50° e. g. 38° to form a ramp in at least one track. When the wiper travels across the

ramp, it disengages from the surface and thereby can be stored or parked at e. g. the ends of the tracks when not in use. Disengaging the wiper from the surface can prevent problems with the wiper bonding to the surface when not in use. The lifetime of the wiper is thus typically lengthened and damage or marking of the surface is typically reduced.

In a modified embodiment, the movement of the wiper follows a arcuate path around a pivot point. The pivot point is preferably at one end of the wiper blade and the drive means can comprise a motor or other drive means which rotates the wiper around the pivot point.

The other end of the wiper can travel on tracks if desired but can be unattached in certain embodiments.

The wiper can be axially extendable in some embodiments, particularly to allow for passage of the wiper over irregularly shaped surfaces. For example, in some embodiments, the wiper can be telescopic and can retract and/or extend to cover the whole surface of e. g. a rectangular or kite-shaped window when moved around a single pivot point attaching one end of the wiper to a corner of the window.

The movement of the wiper can be partially linear and partially arcuate in some embodiments e. g. by having more than one pivot point.

The drive means can be electrically powered or can simply be a form of belts, gears, cogs and drive chains driven by hand by an operator. However, in high or

inaccessible surfaces, electrical or electronic controls and drive means may be suitable.

In one embodiment of the invention the drive means simply comprises a belt or cord arranged in one or more endless loops to which the wiper is attached on the outer surface of the window and having a portion available on the inside of the window to allow the loop to be moved by hand or remotely in order to move the wiper over the outer surface of the window. In that embodiment, gears, wheel or cogs etc on which the belt or cord moves are optional and the drive means may function adequately with only simple bearing surfaces such as nylon bushes over which the cord or belt slides. In a preferred embodiment bushes are provided on the inner surface of the widow frame and rollers are provided on the outer surface.

The drive means may optionally be provided with a handle to move the cord or belt by hand. Typically the handle is urged against the opposite surface of the material to that being wiped, and may comprise a material e. g. a chamois. Said surface is typically polished when the handle is pushed across the surface of the material (typically to activate the wiper to move in the opposite direction on the opposite surface). Alternatively the cord may simply be moved by hand direct.

In certain embodiments of the invention, a fluid conduit is provided to spray or otherwise convey fluid onto the surface being wiped. Typically, the fluid

conduit terminates in a spray head allowing the fluid to be dispersed over the surface. The fluid conduit can also terminate in the wiper itself so as to continuously spray fluid onto the surface in the vicinity of the wiper.

An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings in which: Fig. la is a front view of a window embodying the invention; Fig. lb is a plan view of components of a jamb of the Fig. la window; Fig. 2 is a front view of apparatus of the invention; Fig. 3 is a plan view of the Fig. 2 apparatus; Fig. 4 is a side view of the Fig. 2 apparatus; Figs 5 a, b and c are front, plan and side views of a second embodiment of a window; Fig. 6a is a front elevation of a second embodiment of the apparatus; Fig. 6b is a side elevation of the second embodiment of the invention;

Fig. 6c is a perspective view of the corner of the Fig. 6a embodiment; Fig. 7a is a front elevation of a third embodiment of the invention; Fig. 7b is a side view of the Fig. 7a embodiment; Fig. 7c is a plan view of the Fig. 7a embodiment; Fig. 7d is a magnified view of the Fig. 7a embodiment; Fig. 8a is a perspective view of the apparatus of the third embodiment of the invention; and, Fig. 8b is an end view of the second embodiment of the invention.

Referring now to the drawings, a window comprises a pane of glass 1 and a frame 4. The frame 4 has upper and lower cross members 4c and jambs 4j. A track 6 is fastened to the front face of each of the jambs 4j.

Track 6 each have side channels 6v in the form of a v shape along their length (shown in the plan view of Fig. lb). Each of the tracks 6 has a carriage 8 mounted thereon shown in plan view in Fig. lB and having v shaped feet 8v which engage in the channel 6v in the tracks so as to lock the carriages 8 to the tracks 6 and to allow each carriage 8 to slide longitudinally along its track 6.

In the Fig. 1 embodiment, the carriages 8 are mounted at either end of the wiper 10 which is perpendicular with respect to the tracks 6. However, imprecise alignment of the opposite carriages 8 would hinder the smooth movement of the wiper across the window, and precise alignment of the carriages 8 may be difficult or time consuming. Therefore a degree of slack is allowed in the connection between the carriages 8v and the track channel 6v to allow the carriages 8 a small degree of movement along the tracks 6 independently of each other. This allows the wiper 10 to move freely when the two carriages 8 are slightly offset.

The tracks 6 and the carriages 8 are preferably made of nylon in order to provide a bearing surface but other plastics can be suitable. In particular, in certain embodiments of the invention, the jambs 4j have integrally moulded tracks 6 on their outer surfaces, and can be moulded from UPVC or similar such material.

It is sufficient for the channels 6v and the feet 8v to have nylon or other bearing surfaces, and the remainder of the track 6 and/or carriage 8 can be formed from some other material.

Between the carriages 8 on the respective rails 6 a wiper blade 10 extends. The wiper blade 10 terminates in a u-shaped portion which holds a rubber wiper 11 against the glass pane 1.

One of the tracks 6a has a drive wheel 16 at each end of the outer most surface. The upper drive wheel 16a drives an endless tooth belt 17 which is attached to

the carriage 8a. The carriage 8a can in fact join the two ends of the belt 17, and can incorporate a belt tensioning device 18 which can abut against the outer surface of the belt 17 and can move laterally parallel to the axis of the blade 10 towards the centre of the track 6a in order to tension the belt 17 if required.

The belt 17 can be driven by one or both of the drive wheels 16.

In the embodiment shown, the belt 17 is driven by the upper drive wheel 16a, the lower drive wheel 16b being free to turn without power. Drive wheel 16a is connected to a splined shaft 20 which extends through the track 6a and the jamb 4j terminating in a drive wheel 25 which can be driven by a ball chain common in the art.

Rotation of the shaft 20 rotates the drive wheel 16a, turning the belt 17 around its path between the drive wheel 16a, 16b, and moving the carriage 8a up and down the axis of the track 6a. This moves the blade 10 between the top and bottom of the window plane 1, and drags the wiper 11 across the glass surface. The carriage 8a is connected to the belt 17 at only one position (8c).

In the uppermost cross bar 4c, a hose 30 extends through the cross bar 4c terminating in a spray attachment 30s directed at the pane 1 and disposed at a location preferably beneath the uppermost position of the wiper 10 and carriage 8 assembly. The hose 30 terminates on the inner surface in a ball valve 32

through which fluid can be pumped under pressure e. g. from a pressurisable container containing detergent and water through the hose 30 and spray head 30s onto the glass pane 1 beneath the wiper blade 10.

In use, the blade 10 is moved to the top of the window 1 to a position above the spray head 30s. Water and detergent is then sprayed through the spray head 30s towards the window pane 1 to cover as large an area of the pane as possible, and the drive wheel 25 is then rotated to rotate the shaft 20, drive head 16a and belt 17 in order to move the carriage 8 and drive head 10 assembly so that the rubber wiper 11 is dragged across the wet surface of the window pane 1. The blade 10 and carriage 8 can be moved up and down as many times as are necessary to clean the window, and the hose 30 can be used to spray water and detergent etc onto the window blade above or below the blade 10. If, for example, dirt is concentrated on one area of the window pane 1, the blade 10 may be moved over this area by the operator as many times as necessary without wiping the rest of the window. Such embodiments are therefore more convenient to operate. In certain embodiments the hose 30 can be rotated on its axis through the wall in order to move the spray head 30s away from the front of the window and to prevent water etc collecting in the spray head.

The Fig. 5 embodiment differs only in the detail of the drive means and wiper. The similar frame has been numbered in accordance with the previous embodiments for clarity, with the Fig. 5 reference numbers being

the same as analogous parts in the previous embodiments + 100.

The fig. 5 embodiment is much simpler and has an optional pair of tracks 106 with one track 106 attached to a respective jamb 104J. The wiper 110 has a blade 111 of rubber which is urged against the pane 101 by a foam backing (not shown) under the blade 111. The carriages 108 each carry the respective ends of wiper 110 on an endless cord 117 between top 116a/116c and bottom 116b/116d rollers. A spring (not shown) may be provided between each carriage 108 and the wiper 110 to maintain the pressure of the wiper 110 against the window pane 101. Each cord 117 passes through an aperture 90 adjacent a respective roller 116 to the inner face of the window frame 104, where a nylon bearing bush 95 faces off the inner face of the aperture. The bush 95 has a stem which extends into the aperture and a head which lies against the inside surface of the jamb 104j so that the cord passing through the bush 95 encounters little friction. A roller or a bush can be used at the inner or outer surface of the window. The ends of the cord 117 are attached to a handle 96 on the inner face of the window which can be moved by a user up and down to move the wiper 110 and blade 111 against the pane 101 in the opposite direction. The fluid conduit 130 functions as before.

The cord 117 may be steel wire and may be coated with UPVC or any other suitable material.

The carriages 108 can be captive on tracks 106 or can be free to move without tracks; the wiper blade 111 being held against the pane 101 by the force of the cord 117 and the foam backing.

The handle 96 is optional since the cords 117 can simply be grasped and moved up and down as required.

The cords 117 can be moved by hand or by motor as previously described.

The handle 96 may optionally comprise a chamois or other suitable material such as a duster, cloth etc; which is urged against the inner face of the pane 101.

As the handle 96 is pushed across the inner surface of the window 101 (to activate the wiper 111 to move in the opposite direction on the opposite surface), the chamois polishes the inner surface of the window.

When the wiper is not in use it is typically left at the top or bottom of the window pane 201 so that the view through the window is not unnecessarily obscured.

If the wiper is left for long periods of time on the pane, the rubber may bond thereto which reduces the lifetime of the wiper and may mark the window. In the fig. 6 embodiment the guides 206 are optionally directed away from the plane of the window at 266 and 286-adjacent to the top and bottom of the pane-and so allow the wiper to be parked without contact with the window when not in use. The associated problems with the wiper bonding to the window and damage to the surface of the window are thereby avoided.

Typically the tracks will be mounted on the longest side of the window frame so that the wiper traverses the shortest side possible. For example, for rectangular windows which extend horizontally, it may be impractical to mount a wiper horizontally across the window simply because of its long length. A series of smaller wipers may be mounted on vertically extending tracks but such tracks may obscure the window and the extra wipers may increase the cost for the apparatus.

Therefore, in some embodiments the tracks may be placed at e. g. top and bottom cross members instead of the side jambs. A cost saving may then be made for windows which extend horizontally as smaller wipers may be employed. One of the other advantages is that the apparatus may be employed for windows of many different shapes and sizes without obscuring the view through the window. The mechanism for wiping the window in such embodiments may be any of the mechanisms described herein.

Modifications and improvements can be incorporated without departing from the scope of the invention. For example, the belt 17 and drive head 16 can be located underneath the track 6 in order to hide the mechanical aspects from the front view of the building. Similarly, the blade 10 can be parked at a position on top of the upper or lower cross member 4C in order to avoid obstructing the view out of the window. One or more of the drive heads 16 can be mounted in slots (not shown) in order to permit large adjustments in the tension of the belt 17. Slots can also be used in the attachments for the tracks to allow for later corrections in

alignment of the tracks. The spray head 30s can be moveable either through rotation of the hose 30 or by translocation of the spray head 30s itself up and down the outer face of the window 1. The drive head 16 can be mounted on sealed bearings 15 where the shaft 20 passes through the window frame, and the inner bearing 14 can support the inner drive wheel 25.

Many different types of drive means can be used, for example, electric motor, hand operated, worm screws and bevel gears, ball screws, and chains/cog based drive systems are very suitable.

A third embodiment of the apparatus is shown in Figs. 7 and 8. In this embodiment, one track is replaced by a fulcrum 351 which pivotally connects to a double bladed wiper 310a, 310b. The blades 311a, 311b are attached to the respective wipers 310a, 310b by any suitable means such as a snap fit connection or adhesive. The wiper 310b is positioned inside the wiper 311a and may axially extend therefrom in a telescopic manner as shown in Fig. 8a. The wiper 311b is pivotally attached to carriage 308 by a fulcrum 350. A hose 330 extends through a window pane 301 and comprises a one-way ball valve 332 and a nozzle 330s through which fluid is conveyed onto the window as described above for other embodiments.

A single belt and cog mechanism such as those employed for either of the previous embodiments is provided to activate and move the carriage 308 and will not be described further.

In use the carriage 308 is activated to move along the track 306. The wipers 310a, 310b pivot around point 351, and around pivot point 350 with respect to the carriage 308. The wiper 310b is compressed in a telescopic manner into the wiper 310a as they approach the window's median. Thereafter the wiper 310b extends from the wiper 310a in a similar fashion. As the blades 311a, 311b are in contact with the window at all times (unless parked as described herein above for previous embodiments) the whole area of the window 301 is thereby wiped. The wiper 310b may be spring-loaded to aid its axial extension from the wiper 310a.

A combination of tracks and pivots may be employed to wipe trapezium-shaped or other similar off-sized windows. An advantage of the double wiper is that the complete surface of such irregular sized windows may be wiped.

In other embodiments tracks are not provided. The wiper blade 310 is simply restrained at the pivot point, and driven in a pivotal manner from that pivot point by the means already described.

The apparatus of certain embodiments typically extends only a few centimetres from the window pane and so do not compromise the aesthetic appeal of the windows.

Moreover, certain embodiments of the invention are minimally obstructive and may be mounted on the inner face of the window if so required without obstructing the use of the window sill or protruding dangerously.

Such embodiments are also suitable for other applications where the distance that the wiper extends is significant e. g. mounted to window frames which would normally be protected by bars. Such windows are typically difficult to clean since access is restricted by the bars and the distance between the window pane and the bars is often small.