AU664947B2 - Extraction devices for cleaning equipment - Google Patents

Description

-1- EXTRACTION DEVICES FOR CLEANING EQUIPMENT Field of Invention The present invention relates to cleaning equipment in general and, in particular, discloses an extraction devices used to perform water extraction cleaning of floor coverings and other surfaces.

Background Art There are presently available in a large variety of cleaning equipment used for household and industrial cleaning. Such devices range from a domestic vacuum cleaner which performs a dry cleaning function, for example of carpet, by applying suction to the carpet surface generally using a head or nozzle arrangement. In some instances, a head can be supplemented by a brush which can be caused to rotate by the flow of air into the head through a suction force provided by a fan motor or the like.

Another class of cleaning equipment is those that utilise water extraction and these devices predominate in industrial cleaning situations and are generally used 15 periodically in domestic situations to achieve a more thorough cleaning operation than that achieved with a domestic vacuum cleaner. A water extraction arrangement .".involves the spraying of a fluid onto the surface being cleaned, the fluid typically being water, but sometimes being supplemented by a shampoo or other cleaning agent. The fluid acts to dampen the surface being cleaned and therefore any dirt and the like that may be attached or ground into the surface. The water based cleaning equipment operates to extract the fluid from the surface generally utilising two wiping edges between which closed orifice suction acts to draw the fluid from the surface being cleaned, which again is typically carpet but can be smooth surfaces such as linoleum, tiles and like.

There are a large variety of water based extraction cleaning devices in the market place today and they include handheld wands which include an extraction head which is contacted onto the surface being cleaned, the wand being conlected to a vacuum source which in some configurations can be mounted on a truck. Other n:\liboo0lO246:LODP arrangements include integral extraction devices such as rotary cleaning head equipment which are motorised self-contained units that can be walked over a surface being cleaned under control of an operator.

A major disadvantage of water-based extraction equipment currently in use is particular evident when cleaning carpet. The disadvantage lies in that the carpet is typically damp after the cleaning operation for a period of between four to six hours.

Usually, damp carpet should not be walked upon or otherwise used as any dirt that may be carried on to the carpet is more likely to be retained in the carpet through contact with the moisture lying therein.

t10 One attempt to overcome this problem has been to actively promote drying of

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the carpet after water based cleaning. Typically, this involves utilising a separate Sheating device which circulates warm air about the room immediately after the cleaning operation. Such an arrangement however increases the time at which an operator must remain at a particular location prior to moving onto another cleaning location, as well 15 as also increasing the cost of equipment to be purchased and operated.

o. oSummary of the Invention In accordance with the present invention there is disclosed an extraction device o S* for fluid based cleaning equipment, the device comprising at least two edges configured to engage a surface to be cleaned, said edges defining therebetween an area from which 20 detritus material and fluid can be extracted from the surface, said edges being operably moveable during cleaning operations in a direction toward fluid applied to the surface, Jo, -or(AeJ ter6 wherein one of said edges/ tdes a plurality of channels configured to permit positive ventilation of air across the surface and into the area to thereby draw the detritus material and fluid from the surface.

In:\llboo00D246:IAD Generally, the applicator is a spray jet by which the fluid, which is typically water and/or a detergent, is sprayed onto the surface.

The channels can comprise slots in the one edge, or alternatively apertures through or near the one edge. Typically the other edge(s) acts to wipe the surface so that the fluid accumulates within the area. The channels are typically of substantially rectangular or substantially semi-circular transverse cross-section.

The device can form part of an extraction head of a cleaning wand where the edges connect to closed faces that couple via a tubular stem to a source of negative pressure.

Alternatively, the device can be a shoe of an extraction head for a rotary cleaner. Other configurations are also possible. Preferably the summed cross-sectional area of the channels substantially matches the cross-sectionel area of the stem via which negative pressure is applied.

.:.ooi Brief Description of the Drawings to: 15 A number of embodiments of the present invention will now be described with reference to the drawings in which: Fig. 1 illustrates a side view, partially in cross-section, of an arrangement of a first embodiment; Fig. 2 is a rear perspective view of an extraction head of a second embodiment; Fig. 3 is a rear perspective view of an extraction head of a third embodiment; SFigs. 4 and 5 illustrate a preferred arrangenient for modifying a conventional extraction head to operate in accordance with an embodiment of the invention; Figs. 6 to 11 are respectively perspective, plan, inverse plan, front elevation, rear elevation and right side elevation views of an extraction head in accordance with the preferred embodiment; Fig. 12 illustrates a rotary jet extraction device of another embodiment; Fig. 13 is a view of the underside of the device of Fig. 12 illustrating the arrangement of the extraction heads; and n:\lIfboolOO246:LDP Fig. 14 is a exploded perspective view of one extraction head of Figs. 12 and 13.

Detailed Description Fig. 1 is a side, partially sectional view, of a extraction tool 1 which has a tubular stem 2 connected to an extraction head 3 via a coupling 4. The tubular stem 2 is typically connected to source of negative pressure such as a high powered vacuum or suction device such as that typically used in carpet cleaning applications and the like.

The tool 1 includes a spray nozzle 5 mounted adjacent the coupling 4 and is supplied with a feed line 6 by which a spray 7 of cleaning fluid, such as water and/or detergent can be applied to a floor covering 8 such as carpet. Other materials such as upholstery and curtains can be cleaned in a similar manner.

The extraction head 3 includes a front face 9 and a rear face 10 between which a channel 15 is defined which acts as a passage for the transportation of dirt particles and oo *o the like from the carpet 8 at an opening area 18 of the channel 15 through the coupling 4 and into the stem 2. In operation, the extraction tool 1 is moved in the direction of Sthe arrow 11 by means of an operator pulling or drawing upon a periphery (not seen illustrated) of the stem 2. Whilst pulling the extraction tool 1 in the direction 11, the spray 7 acts to dampen sections of dirty carpet 16 over which the extraction head 3 is to pass. The front face 9 and rear face 10 are triangular or trapezoidally-shaped and inclined to one another such that the cross-sectional area of the channel 15 is ""substantially constant along its length, and substantially corresponds, and is preferably identical, to the cross-sectional area of the tubular stem 2. In this manner, vacuum pressure is applied evenly across the opening area 18.

The extraction head 3 includes, in the rear face 10, a number of apertures 12 (better seen in subsequent figures in relation to other embodiments) arranged near the periphery, or edge of the face 10 that engages the carpet 8. The apertures 12 provide a passage for air to be drawn into the channel 15 as a result of the negative pressure being applied through the stem 2. The air passing through the apertures 12 provides [n\liboo100246:LDP for positive ventilation as indicated by the arrows 13 which act to transport away from the carpet 8 dampened dirt particles 14 and the like. As the extraction head 3 is moved over the damp and dirty carpet 16, the cleaning liquid and dirt 14 is removed to leave the carpet 17 upstanding and substantially dry.

It will be apparent from Fig. 1 that the apertures 12 are provided in the edge of the face 10 interposed between the spray 7 and he edge of the face 9, such that the apertures 12 are exposed, when the tool 1 is moved in the direction 11, to freshly dampened carpet. In this manner the edge of the face 9 adjacent the opening area 18 acts to wipe the carpet 8 to ensure that any moisture is accumulated within the opening area 18 and channel 15 whereupon the positive ventilation afforded by vacuum pressure acts to draw that water away from the carpet 8.

The arrangei-ent shown in Fig. 1 operates in a quite different manner to "1 "conventional extraction heads. In conventional extraction heads, the apertures 12 are not provided, and the front face 9 and rear face 10 each engage the carpet or other S° :i 15 surface material being cleaned. Because of the relatively high negative pressure applied °in conventional vacuum arrangements, a high amount of suction is provided at the carpet. However, because entry of air into the conventional head is substantially :limited, due to the need for the air to pass through the carpet, little or no flow of air occurs within the conventional head. Therefore, the large negative pressure, whilst exerting reasonable force upon the dirt particles and carpet alike, does little to actively draw dirt particles and cleaning liquid away from the carpet. Typically, after cleaning operations with conx entional equipment, the carpet remains wet for between four to six hours. Furthermore, when in use a typical exhaust air speed of a conventional cleaning ipparatus is approximately 25 miles per hour (40km/hr). This is to be contrasted with an open orifice exhaust speed of 72 miles per hour (116km/hr) when the conventional cleaning head is lifted from the carpet. The foregoing speeds are measured using 12 inches of mercury vacuum applied to the cleaning head.

(n:\llAboo100246:LDP Turning now to Fig. 2, an extraction head 20 is shown which includes a trapezoidal rear face 21, an outlet coupling 22, side walls 23 and a trapezoidal front face 24. As seen, the rear face 21 is provided, at its lower edge which is configured to engage with the carpet or other material being cleaned, with array of semi-circular channels, slots or scallops 25 which communicate into the interior of the head 20, and to the outlet coupling 22. The scallops 25 act in the same manner as the apertures 12 to provide positive ventilation into the extraction head 20 to assist in carriage of water and dirt particles away from the material being cleaned.

Fig. 3 illustrate an extraction head 30 having a rear face 31, outlet coupling 32 side walls 33 and a front face 34. Like the previous embodiment, the extraction head is provided with a number of slots 35, which in this embodiment are square in crosssection which, as before act to provide positive ventilation into the interior of the extraction head In each of the extraction heads 20 and 30, the amount of positive ventilation 15 provided to the head can be controlled through a selection of the size of the scallops and slots 35 respectively. Most preferably, to obtain an optimised flow, and therefore cleaning of the carpet 8, the sum cross-sectional area of the scallops 25 or slots substantially matches the cross-sectiona;l area of the corresponding outlet coupling 22 and 32 respectively. In this manner, any negative pressure applied to the couplings 22, 32, acts not to provide suction at the carpet surface, but rather total positive air flow ***across and through the carpet which acts to lift the pile as well as move dirt particles and dry the carpet.

The arrangements illustrated in Figs. 1 to 3, whilst in accordance with the invention, are not wholly preferred because the structure of the apertures as illustrated provides a number of relatively sharp edges which would make such heads inconvenient for use in cleaning longer pile carpets and especially loop pile carpets.

Figs. 4 and 5 illustrate an alternative arrangement by which the configuration of Fig. 2 can be achieved through modification of a conventional extraction head.

[n:;liboo00O246:LDP Fig. 4 shows a front face 50 and a rear face 51 of a conventional cleaning head.

i_ Aed to the lower periphery of the front face 50, by means of a number of welds 41, is a rod 40 preferably manufactured out of 5mm diameter 316 stainless steel.

Arranged and attached to the periphery of the rear face 51 by means of a number of welds 43 is a rod 42 manufactured of the same material into which a plurality of scallops 44 have been ground. As seen in Fig. 5, the grinding of the scallops 44 from the rod 42 provides the rod 42 with a plurality of smooth edges 45 thereabouts which therefore are not inclined to become caught upon the material being cleaned and, in particular, loop pile carpets. It will be appreciated from the foregoing that the addition of the rods 40 and 42 to the periphery of a conventional cleaning head modifies that head to operate in accordance with the preferred embodiment to permit positive ventilation within the head. As before, it is preferred that the cross-sectional area of the scallops 44 be matched to the cross-sectional area of the outlet coupling (not 9 V.0 °illustrated, but corresponding to that of the previous embodiments).

0 1 The use of the rods 40 and 42 provides a further advantage in that over a 9..

number of years the head may become worn. Accordingly, the rods 40 and 42 of Figs.

4 and 5 can, once worn, be removed by breaking the welds 41 and 43 whereupon new, replacement rods 40 and 42 can be welded onto the head. Such an arrangement permits the repair and refurbishment of an otherwise serviceable extraction tool.

As best seen in Fig. 5, a side face 46 of the extraction head is configured to extend down beside the rods 40 and 42 so as to seal the channel therebetween and only to permit positive ventilation through the scallops 44. Furthermore, because the welds 41 and 43 are only interspersed along each of the respective faces 50 and 51, any openings between any two welding locations is preferably sealed using a silicone sealant 47 or the like.

Figs. 6 to 11 provide various views of an extraction head 60 of the preferred embodiment. The head 60 includes a substantially triangular front face 61 and a similarly shaped rear face 62 which unitarily connect to a tubular outlet stem 63. As [n:\liboolOO24G:LDP seen in Figs. 8 and 10, extending downwardly from the stem adjacent the rear face 62 is a threaded support 64 upon which a spray nozzle or similar component can be mounted. Associated with this configuration are spray guards 65 and 66 arranged to confine any sprayed fluid upon the surface being cleaned adjacent the rear face 62. The faces 61 and 62 end in respective edges 67 and 68, the latter being provided with channels 69 which permit positive ventilation into a channel 71 formed between the two faces 61 and 62. A nut and bolt arrangement 70 is provided to interconnect between the front and rear faces 61 and 62 to ensure a predetermined separation therebetween.

Like the previous embodiments, the slots 69 are interposed between the position of the spray nozle and the wiping edge 67 to ensure positive ventilation across those damp surfaces being cleaned.

Experiments by the present inventor have indicated that the arrangement of the 0 preferred embodiment provides for an increase of efficiency of between 35 to when compared to conventional cleaning equipment. Furthermore, when correctly 15 used, carpet cleaned with extraction heads of the preferred embodiments can be left dry to within approximately one hour.

o With the arrangement of the preferred embodiment, positive ventilation provided S-by the channels 69 provides an exhaust air speed of 45 miles per hour (72km/hr) when the extraction head 60 is applied to carpet that speed being measured using 12 inches of 0 mercury vacuum applied to the cleaning head. This represents a significant speed increase over that of a conventional cleaning head mentioned previously. The preferred embodiment operates with air flow rates of between 300 and 500 cubic feet per minute (8,100 13,500 litres/minute).

Fig. 12 illustrates a self-contained rotary jet extraction unit 100 which includes an on-board motor source 101 and operator controls 102. Power is supplied via an electric cord input 103 and the unit 100 also includes integral filter devices such that it may provide a clean air output port 104.

In:\lWboolOO246:LDP -9- As best seen in Fig. 13, the extraction 100 includes five extraction heads 105 each connected to a star shaped plate 106 configured to rota*- through operation of the motor 101 in the direction indicated by the arrows 107. Extending from each of the extraction heads 105 is a flexible duct 108 configured to transport away from each of the heads 105 and detritus material, water particles and the like to filtering devices within the extraction unit 100.

Associated with each of the extraction heads 105 is a corresponding spray nozzle 109 configured to spray cleaning fluid such as water onto the surface being cleaned into the path of the respective extraction head 105.

1o As best seen in Fig. 14, each of the extraction heads 105 includes a body portion 110 preferably cast from aluminium, steel or a suitable alloy, and which provides a coupling 111 for connection to the duct 108. The head 105 also includes a shoe 112 toeo a from which a pair of threaded posts 115 extend and that are arranged to pass through o0: corresponding apertures 119 in the body 110 for fastening using a nut and washer 15 arrangement 116. The shoe 112 includes a leading beam 114 which is slightly upturned 0 999.9.

so as to cause the shoe 112 to ride up and over and across rough or thick surfaces, such as loop pile carpet. Included also within the shoe 112 is a rearward wiping edge 113 and an intermediate edge 117 provided with scallop-shaped channels 118 which permit positive ventilation of air into an area 120 and through into the body 110 and o from the coupling 111 as a result of vacuum pressure provided by the motor unit 101.

As with the preceding embodiments, the nozzles 109 precede the positive ventilating intermediate edge 117 such that a wiping action can be performed by the trailing edge 113. As with the previous embodiment, once the shoe 112 is assembled onto the body 111, any gaps between either of the edges 117 or 113 can be filled using a silicone sealant or like substance.

The foregoing describes only a number of embodiments of the present invention and modifications, obvious to those skilled in the art can be made thereto without departing from the scope of the present.

ln:\llboo100246:LDP For example, other types of water extracting units can be configured to operate in accordance with the present invention. For extraction, rotary brush machines can be arranged with a ventilating edge and a wiping edge following the rotating brush so as to capture any water or detritus material disturbed by the motion of the brush during its cleaning operation. The invention can also be applied to other devices in a similar manner.

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Claims (31)

1. An extraction device for fluid based cleaning equipment, the device comprising at least two edges configured to engage a surface to be cleaned, said edges defining therebetween an area from which detritus material and fluid can be extracted from the surface, said edges being operably moveaule during cleaning operations in a direction toward fluid applied to the surface, wherein one of said edgesitekHdes a plurality of channels configured to permit positive ventilation of air across the surface and into the area to thereby draw the detritus material and fluid from the surface.

2. An extraction device as claimed in claim 1 wherein said fluid is liquid. 10 3. An extraction device as claimed in claim 2 wherein said liquid comprises water andor detergent.

4. An extraction device as claimed in claim 1, 2 or 3 further comprising applicator means by which the fluid can be applied to the surface. An extraction device as claimed in claim 4 wherein said applicator means 15 comprises at least one spray nozzle configured to direct said fluid onto said surface. g 6. An extraction device as claimed in claim 4 or 5 wherein said applicator S, means is positioned adjacent said one edge.

7. An extraction device as claimed in claim 6 wherein said one edge is arranged between said applicator means and the other of said two edges. S 20 8. An extraction device as claimed in claim 7 wherein said device is operatively movable in a direction toward the fluid applied to the surface to thereby draw air across wetted portions of the surface, through said channels, and into said area, said other edge acting to wipe the surface to accumulate the fluid within said area.

9. An extraction device as claimed in any one of the preceding claims further a comprising an outlet port in communication with said area and by which negative pressure is applied to said device. [n:\llboo]00246:IAD -12- An extraction device as claimed in any one of the preceding claims further comprising a communication channel arranged between said two edges and said outlet port.

11. An extraction device as claimed in claim 10 wherein said device comprises a body portion including said communication channel and said outlet port, and said edges are connectable to said body portion to define said area.

12. An extraction device as claimed in claim 11 wherein said edges are removably connectable to said body portion.

13. An extraction device as claimed in claim 12 wherein said edges are unitarily formed, and thereby unitarily removably connectable to said body portion. o•14. An extraction device as claimed in claim 11, 12 or 13 wherein said edges are removably connectable to said body portion by means of a securing arrangement. An extraction device as claimed in any one of claims 11 to 1.4, wherein said one edge comprises a first rod in which said channels are formed, said first rod is being interconnected to a second rod substantially parallel thereto to form the other said edge and said area therebetween, and a seci arrangement comprises a pair of threaded posts arranged to extend from interconnections between said rods to pass through correspcnd..g apertures in said body portion and to be secured thereto by corresponding nuts. S 20 16. An extraction device as claimed in claim 11 wherein said edges are S° connectable to said body portion by welding, said edges and said body portion being manufactured of materials permitting interconnection by welding.

17. An extraction device as claimed in claim 11 or 16, wherein said body portion comprises a first face upon which said one edge is formed, a second face upon which the oth r of said edges is formed, and ends interconnecting the faces, said outlet port comprising a tubular stem extending from said first face and communicating between said communication channel formed between said faces and said ends to a source of negative pressure connectable to the stem. In:\llbool00246:IAD -13-

18. An extraction device as claimed in claim 17 when dependent on claim wherein said spray nozzle depends from said stem adjacent said first face to direct fluid onto the surface adjacent said one edge.

19. An extraction device as claimed in any one of claims 11 to 18 wherein said edges are manufactured from stainless steel. An extraction device as claimed in any one of claims 11 to 18 wherein said body portion is manufactured of materials selected from the group consisting of stainless steel, cast steel, cast aluminium, and a cast suitable alloy. .g

21. An extraction device as claimed in any one of the preceding claims 10 wherein said channels are substantially rectangular in transverse cross-section. S..

22. An extraction device as claimed in any one of claims 1 to 20 wherein said channels are substantially semi-circular in transverse cross-section.

23. An extraction device as claimed in claim 21 or 22 when dependent on claim 9 wherein the sum transverse cross-sectional area of said channels substantially matches the transverse cross-sectional area of said outlet port.

24. An extraction device as claimed in claim 21, 22 or 23 when dependent on claim 10 wherein said communication channel is shaped such that its transverse cross- sectional area along its length substantially matches the transverse cross-sectional area of said outlet port. 20 25. An extraction device for fluid based cleaning equipment, the device &:Soo: comprising at least two edges configured to engage a surface to be cleaned, said edges defining therebetween an area from which detritus material and fluid can be extracted from the surface, one of the edges being positioned adjacent an applicator by which the fluid is applied to the surface, said edges being operably moveable during cleaning operations in a direction toward fluid applied to the surface, wherein said one edge includes a plurality of channels configured to permit positive ventilation of air across the surface and into the area to thereby draw the detritus material and fluid from the g-7 surface. Sr1 tn:\llbaoo00240:lAD -14-

26. An extraction device as claimed in claim 25, wherein said channels are substantially rectangular or semi-circular in cross-section, and the sum cross-sectional area of the channel substantially matches the cross-sectional area of an outlet port of said device via which a negative pressure is applied to said device.

27. An extraction device as claimed in claim 25, further comprising a first face upon which said one edge is formed, a second face upon which a wiping edge is formed, and ends interconnecting the faces, a tubular stem extending from said first face and communicating between a flow passage between the faces commencing at the e area, to a source of negative pressure connectable to the stem, and a spray nozzle orolo depending from the stem adjacent the first face to direct fluid onto the surface adjacent said one edge. i Ot ~28. An extraction device as claimed in claim 25, wherein said one edge 4 comprises a first rod in which said channels are formed, said first roa being interconnected to a second rod substantially parallel thereio to form the other said edge, o 15 and a securing arrangement by which said rods can be attached to a body portion via which negative pressure can be applied to said area between said rods.

29. Fluid based extraction apparatus comprising: a source of negative pressure; at least one extraction device as claimed in any one of the preceding claims S 20 interconnected to said source to apply said negative pressure at said area to draw air *:othrough said channels. A method of liquid-based cleaning of a surface, said method comprising the steps of: applying liquid to said surface to at least dampen a section of said surface; applying negative pressure to an area of the section, said area being defined by hCIL -C AAA~kA at least two edges in contact with said surface, one of said edgesAokn a plurality of channels configured to permit positive ventilation of air across said surface and through SRA, said channels to draw said liquid and detritus material from said surface. In:\llboo100240lAD 4W

31. A method as claimed in claim 30 wherein said liquid comprises water and/or detergent.

32. A method as claimed in claim 30 or 31 wherein said liquid is applied to said section adjacent said one edge.

33. A method as claimed in claim 30, 31 or 32 wherein said edges comprise part of an extraction device coupled to a source of said negative pressure, said extraction device further comprising an outlet port, and a communication channel interconnecting said area and said outlet port.

34. A method as claimed in claim 33 wherein said extraction device is too*&: S10 operatively movable across said surface toward said section, whereby said one edge k° o s ee •interposed between said action and the other said edge, said other edge acting to wipe said surface to accvmulate said liquid within said area. A method as claimed in claim 33 or 34 wherein said extraction device further comprises at least one applicator for applying said liquid to said surface. 15 36. A method as claimed in any one of claims 30 to 35 wherein the step of S 'o applying said negative pressure comprises applying the negative pressure evenly across said channels.

37. A method as claimed in claim 36 wherein a sum transverse cross-sectional area of said channels substantially matches a transverse cross-sectional area of said 20 outlet port. OO•Oe

38. The invention as claimed in any one of the preceding claims wherein only said one edge incorporates said channels.

39. An extraction device for fluid based cleaning equipment substantially as described herein with reference to Figs. 1 and 2 of the drawings.

40. An extraction device for fluid based cleaning equipment substantially as described herein with reference to Figs. 1 and 3 of the drawings.

41. An extraction device for fluid based cleaning equipment substantially as -described herein with reference to Figs. 1, 4 and 5 of the drawings. In:\llboo]OO24O=IAD -16-

42. An extraction device for fluid based cleaning equipment substantially as described herein with reference to Figs. 6 to 11 of the drawings.

43. An extraction device for fluid based cleaning equipment substantially as described herein with reference to Fig. 14 of the drawings.

44. Fluid based extraction apparatus incorporating an extraction device as claimed in any one of claims claim 6 to Fluid based extraction apparatus substantially as described herein with reference to Figs. 12 to 14 of the drawings.

46. A method of liquid-based cleaning of a surface substantially as described herein with reference to any one of the described embodiments. S *DATED this Seventeenth Day of May 1995 Dirt Devil Sales Pty Limited Patent Attorneys for the Applicant SPRUSON FERGUSON [n\llIbool00246:lAD [n;\ibool0024B;IAD ABSTRACT EXTRACTION DEVICES FOR CLEANING EQUIPMENT Disclosed is an extraction device (20) for use with water-based cleaning equipment. The device (20) includes a coupling (22) connectable to a source of negative pressure. The device (20) is characterised by a plurality of channels or apertures (25) arranged in one edge of the device (20) configured to engage a surface to be cleaned. The apertures (25) permit positive ventilation of air across the surface to be cleaned and into the device (20) for exhaust through the outlet (22). C e S .t 4. ln:\lboo)00246:LDP