CLEANING HEAD

Abstract: An elongate cleaning head comprises an outer housing (10) defining a suction chamber and an inner housing (20) affording a cleaning liquid distributing chamber (26) from which liquid flows through closely spaced fine outlets (33) into a liquid delivery chamber (29) at a position spaced from the mouth (25) of the inner housing. The side walls (22) of the inner housing are formed with baffles (24) including upwardly divergent wings (24 a ,24 b ) so that air flow through the suction chamber initially diverges away from the open mouth thereof towards an upper zone (l7) between the upper wall (22 a ) of the inner housing (20) and the upper wall (l3) of the outer housing (10), in which upper zone the air-flow converges to an outlet (11).

Description: This invention relates to a cleaning head for use with an apparatus for cleaning floors, walls, carpets, curtains, upholstery and the like, and more particularly concerns a cleaning head for use in the process of water extraction cleaning, in which a carpet or the like is thoroughly wetted by a solution containing a suitable cleansing agent, such as a non-foaming detergent, and the carpet or the like is then dried by the uptake of that solution by means of suction. Such a cleaning head is the subject of our British Patent No. 1601455 and the present invention concerns a development of the design disclosed therein. GB 1601455 illustrates the basic form of cleaning head to which the present invention is applied and comprises a suction chamber having an open mouth and a centrally disposed outlet for connection to a source of suction, and an inner compartment extending medially within the suction chamber and having a side wall defining an open mouth substantially in the plane of the open mouth of the suction chamber, the inner compartment having associated therewith cleaning liquid distributing means including a plurality of closely spaced fine outlet passageways adapted to allow cleaning liquid to flow into the inner compartment at a position spaced from the mouth thereof. According to the present invention we provide an elongate cleaning head comprising a suction chamber having an open mouth and a centrally disposed outlet for connection to a source of suction, and an inner compartment extending substantially medially within the suction chamber and having side walls defining an open mouth substantially in the plane of the open mouth of the suction chamber, the inner compartment having associated therewith a cleaning liquid distributing chamber formed with a plurality of closely spaced fine outlet passageways adapted to allow cleaning liquid to flow into the inner compartment at a position spaced from the mouth thereof, wherein the suction chamber is divided externally of the inner compartment into two laterally spaced suction zones by means of a central baffle which diverges in a direction away from the open mouth of the suction chamber towards an upper zone of the suction chamber into which upper zone said outlet opens. The divided suction chamber with the upwardly divergent baffle causes the air flow through the head from the open mouth to the outlet to be split into two streams which diverge away from the centre of the head in the respective suction zones and then converge towards the outlet in the upper zone of the head. This arrangement makes it possible to increase the transverse width of the head without reducing the efficiency of the liquid pick-up operation and without increasing the overall air flow requirement. Thus in practice, the use of a cleaning head in accordance with the present invention typically makes it possible to utilise a cleaning head having a width of approximately 20cm (8 inches) without increasing the air flow requirement over that which would otherwise be required for a 12.5cm (5 inch) head whilst maintaining equivalent efficiency of operation. In accordance with a further feature of the invention the inner compartment is formed or provided with a separating wall dividing it into an outer liquid delivery chamber adjacent to said open mouth of the inner compartment and an inner chamber which serves as said liquid distributing chamber, said outlet passageways being formed in said separating wall. Preferably said liquid distribution chamber is so dimensioned to serve as a storage reservoir within the cleaning head, for the cleaning liquid, which reservoir has a height sufficient to create a substantially equal hydrostatic head pressure at each of the outlet passageways. Typically the height of the reservoir may be at least 10 mm. Preferably said liquid distribution chamber has sufficient volume such that when substantially full a substantially equal flow rate of cleaning liquid from each of the outlet passageways can be achieved during application of the open mouth to a surface. Typically, the volume may be approximately 1cc per linear centimetre of the head. The open mouth of the inner compartment is preferably of elongate configuration and said inner compartment preferably extends across the suction chamber substantially parallel to the main axis thereof. The open mouth of said inner compartment is preferably located substantially centrally within the open mouth of the suction chamber whereby air-flow into the suction chamber takes place on both sides of the open mouth of the inner compartment, and the upper side of the body is preferably spaced above the upper side of the inner compartment by such a distance as to allow substantially unrestricted air-flow towards the outlet from both sides of the inner compartment. According to a further preferred feature of the invention said inner compartment may be formed as a separate unit which is removable from the suction chamber, although it may alternatively be formed integrally. The present invention further resides in an inner housing for assembly with a suction cleaning head of the kind comprising a suction chamber having an open mouth and a centrally disposed outlet for connection to a source of suction, the inner housing comprising an elongate body dimensioned for reception medially within said suction chamber and affording an open mouth which when the inner housing is in situ is subtantially in the plane of the open mouth of the suction chamber the housing being formed or provided with a separating wall dividing it into an outer liquid delivery chamber adjacent to said open mouth and an inner liquid distributing chamber having a liquid inlet, said separating wall being formed with a plurality of fine outlet passageways at closely spaced intervals along the length thereof to allow liquid to flow from said liquid distributing chamber into said liquid delivery chamber at a position spaced from the open mouth, characterised in that externally the inner housing is formed or provided with baffles on opposite sides thereof, each comprising a rib of shallow V-shape with two wings diverging in a direction away from the open mouth of the housing. These and other features of the present invention will now be described by way of example with reference to the specific embodiments illustrated in the accompanying drawings wherein:- FIGURE 1 shows a first embodiment of cleaning head in a part-sectional front elevation; FIGURE 2 shows an underneath plan view thereof; FIGURE 3 shows a vertical section on the line III-III of Figure 1; FIGURE 4 shows a second embodiment of cleaning head in a part sectional front elevation; FIGURE 5 shows a vertical section on the line V-V of Figure 4; FIGURE 6 is a side view of an inner housing for cleaning head as shown in Figures 4 and 5; FIGURE 7 is a cross-section on the line VII-VII of Figure 6; FIGURE 8 is an underneath plan view of the inner housing shown in Figure 6; FIGURE 9 is a side view of a T-section bar which fits into the inner housing shown in Figure 6; and FIGURE 10 is an end view of the T-section bar. The first embodiment of cleaning head in accordance with the invention as illustrated in Figures 1 to 3 comprises an elongate outer housing 10 with a centrally disposed tubular outlet spigot 11 for attachment to the suction hose (not shown). The outer housing 10 receives therein a structurally separate medially extending inner housing 20 having side walls 22 which are spaced from the side walls 12 of the outer housing and an upper wall 23 which is spaced from the upper wall 13 of the outer housing. The side walls 22 of the inner housing 20 each carry a shallow V-formation rib 24 including wings 24 a , 24 b which bridge the space between the side walls 22 of the inner housing and the side walls 12 of the outer housing. As can be seen from Figure 1, the wings 24 a , 24 b diverge upwardly away from the open mouth 15 of the outer housing and outwardly from the centre. The ribs 24 serve as baffles whereby the suction chamber defined by the outer housing 10 is divided into two laterally spaced suction zones 16 a , 16 b in which air drawn in through the open mouth 15 is divided into two divergent streams as indicated by the arrows A and B. The ribs 24 terminate at positions approximately half way between the centre line and the end walls 14 of the outer housing, so that the air flows enter an upper zone 17 of the outer housing above the inner housing 20 and converge towards the outlet spigot 11 as indicated by arrows C. The portion of the inner housing 20 adjacent to the open mouth 25 accommodates a T-section bar member 30 whereof the transverse web 32 is received innermost and is supported at the ends of the inner compartment 20 by engagement within recessed portions of the end walls thereof. The central leg 31 of the T-section bar member 30 extends downwardly from the web 32 and terminates in the plane of the open mouth 25 of the inner compartment 20. The lateral edges of the transverse web 32 of the T-section bar member 30 are formed with a plurality of spaced calibrated grooves 33 which extend between each face thereof. The transverse web 32 of the T-section bar member 30 forms a separating wall which divides the inner compartment 20 into an internal liquid distribution chamber 26 above the transverse web 32 and an outer liquid delivery chamber 29 below the transverse web 32, between which chambers communication is provided through the grooves 33. The chamber 26 within the inner housing above the bar 30 has a volume such that it servces as a reservoir for the reception of a cleaning solution which is supplied through a pipe (not shown) to an inlet spigot 21 which protrudes from the inner housing as shown in Figures 1 and 3, whereby when substantially full there is a substantially equal rate of delivery from each passageway 33 under equal hydrostatic pressure. The calibrated grooves 33 are provided at spaced intervals along substantially the entire length of the edges of the web 32 to regulate the flow of liquid so as to cause it to be delivered uniformly and continuously at an appropriate rate. Typically, the apertures 33 have a width of about 0.5 mm and are spaced on 10mm centres. The cleaning solution may be supplied by any appropriate means to the chamber 26, which may typically have a height of at least 1cm and a volume of about 1cc per centimetre of its length. In particular, the head illustrated in Figures 1 to 3 is designed for use with substantially non-pressurised liquid delivery systems. Thus, the liquid may be supplied gravitationally, or by a syphon system, in either case optionally assisted by a slight positive pressure generated for example by the application of exhaust air from the suction cleaner fan to a liquid reservoir in the manner disclosed in our British patent No. 1601456. The space within the inner housing below the transverse flange 32 of the bar 30 defines the liquid delivery chamber 29 which extends medially of the outer housing 10. The arrangement of the end faces of the side walls 22 in the same plane as the mouth of the outer housing 10 ensures that such inner compartment is substantially sealed against the fabric being treated and that there is virtually no possibility of the liquid passing through the grooves 33 being drawn away directly by virtue of the air flow established within the head. Instead, the liquid is shielded by the side walls 22 and is constrained by the side walls to flow onto the fabric being cleaned. In this way, a thorough wetting of the fabric is ensured without spraying. This in turn makes it possible for the appliance to operate with only a low pressure gradient acting on the liquid, and without the need for any pump for the delivery of cleaning liquid to the head under substantial pressure. The divided air flow resulting from the ribs 24 ensures that substantially uniform suction is applied over the entire length of the head, which can thus be made sigificantly greater than in the absence of such ribs without requiring an increase in the overall air flow and without employing a correspondingly more powerful motor to drive the fan of the suction cleaner. As can be seen most clearly from Figure 3 the space above and around the inner housing 20 is such as to provide substantially unimpeded air-flow through the suction chamber on both sides of the inner housing, and over the top thereof into the upper zone 17 of the outer housing 10 and thence to the outlet 11. The second embodiment shown in Figures 4 to 10 is of generally similar form to that of the first embodiment described above and the same reference numerals are used to denote corresponding parts, the following description being largely confined to features of difference. The outer housing 10A of the second embodiment is somewhat deeper than theat of the first embodiment and the inner housing 20A is also deeper than that of the first embodiment with a flat upper wall 23A. The modified inner housing 20A as illustrated in Figures 6 to 10 is generally similar in construction to the inner housing 20 previously described, except in the following respects. The wings 24 a , 24 b of the shallow V-shape ribs 24 do not extend directly to the lower edge of the inner housing, but an additional, vertical wing 24 c extends downwardly from the point at which the wings 24 a , 24 b meet and terminates at the lower edge of the housing 20A. Internal ribs 22 a are formed on the side walls of the housing 20A and terminate as shown at positions spaced inwardly from the open mouth of the housing. The ribs 22 a serve to locate the T-section bar 30 within the housing 20A. Whilst the calibrated air-flow passageway in the illustrated embodiments comprises a pair of small apertures 28 which extend through the upper wall of the inner compartment and open into the upper region of the suction chamber 11, other arrangements are possible. For example there may be a single opening in the upper region of the side wall 22 of the inner compartment 20 in register with the opening afforded by the outlet 14, or a tube may extend from the inner compartment into and along the length of the outlet 14. If desired, the inner housing may be formed as a set of modules which can be interengaged in end-to-end relationship and to be receivable within suction heads of a variety of dimensions as required. By the use of such separate modules, a conventional suction head may be adapted for use for wet cleaning of floor surfaces. Moreover, whilst in the illustrated embodiments a single V-formation rib 24 is formed on each side of the inner housing in a central region thereof, it may be appropriate to provide additional V-formation ribs at positions offset from the central region towards the ends of the housing, particularly for heads of increased width.

Claims: An elongate cleaning head comprising a suction chamber (10) having an open mouth (15) and a centrally disposed outlet (11) for connection to a source of suction, and an inner compartment (20) and extending substantially medially within the suction chamber and having side walls defining an open mouth (25) substantially in the plane of the open mouth of the suction chamber, the inner compartment (20) having associated therewith a cleaning liquid distributing chamber (26) formed with a plurality of closely spaced fine outlet passageways (33) adapted to allow cleaning liquid to flow into the inner compartment at a position spaced from the mouth thereof, wherein the suction chamber (10) is divided externally of the inner compartment into two laterally spaced suction zones (16a, 16b) by means of a central baffle (24) which diverges in a direction away from the open mouth (15) of the suction chamber towards an upper zone (17) of the suction chamber into which upper zone said outlet (11) opens. A cleaning head according to Claim 1 wherein said baffle (24) comprises a rib of shallow V-shape with two upwardly diverging wings (24a,24b). A cleaning head according to Claim 2 wherein said upwardly diverging wings (24a,24b) meet substantially in the plane of the open mouth (15) of the suction chamber (10). A cleaning head according to Claim 2 wherein said baffle (24) comprises a third wing (24c) extending downwardly from the point at which said two wings (24a, 24b) meet and terminating substantially in the open mouth (25) of said suction chamber (10). A cleaning head according to any one of the preceding claims wherein said inner compartment (20) and said baffle (24) are formed as a single unit which is structurally separate from and releasably received in, said suction chamber (10). A cleaning head according to Claim 5 wherein the inner compartment (20) has located therein a structurally separate dividing member (30) which is formed with said fine outlet passageways (38) and divides said inner housing (20) so as to define therein said distributing chamber (26). A cleaning head according to Claim 1 wherein the inner compartment (20) is formed or provided with a separating wall (32) dividing it into an outer liquid delivery chamber (29) adjacent to said open mouth (25) of the inner compartment and an inner chamber (26) which serves as said liquid distributing chamber, said outlet passageways (33) being formed in said separating wall (32). A cleaning head according to Claim 1 wherein said liquid distribution chamber (26) is so dimensioned to serve as a storage reservoir within the cleaning head, for the cleaning liquid, which reservoir has a height sufficient to create a substantially equal hydrostatic head pressure at each of the outlet passageways (33). A cleaning head according to Claim 1 wherein said liquid distribution chamber (26) has sufficient volume such that when substantially full a substantially equal flow rate of cleaning liquid from each of the outlet passageways (33) can be achieved during application of the open mouth to a surface. A cleaning head according to Claim 1 wherein the open mouth (25) of the inner compartment (20) is of elongate configuration and said inner compartment extends across the suction chamber (10) substantially parallel to the main axis thereof. A cleaning head according to Claim 10 wherein the open mouth (25) of said inner compartment (20) is located substantially centrally within the open mouth (15) of the suction chamber (10) whereby air-flow into the suction chamber takes place on both sides of the open mouth of the inner compartment, and the upper side (13) of the body is spaced above the upper side (23) of the inner compartment (20) by such a distance as to allow substantially unrestricted air-flow towards the outlet (11) from both sides of the inner compartment (20). A separable inner housing for assembly with a suction cleaning head of the kind comprising a suction chamber (10) having an open mouth (15) and a centrally disposed outlet (11) for connection to a source of suction, the inner housing (20) comprising an elongate body dimensioned for reception medially within said suction chamber and affording an open mouth (25) which when the inner housing is in situ is substantially in the plane of the open mouth (15) of the suction chamber (10) the housing (20) being formed or provided with a separating wall (32) dividing it into an outer liquid delivery chamber (29) adjacent to said open mouth (25) and an inner liquid distributing chamber (26) having a liquid inlet (21), said separating wall (32) being formed with a plurality of fine outlet passageways (33) at closely spaced intervals along the length thereof to allow liquid to flow from said liquid distributing chamber (26) into said liquid delivery chamber (29) at a position spaced from the open mouth (25), characterised in that externally the inner housing (20) is formed or provided with baffles (24) on opposite sides thereof, each comprising a rib of shallow V-shape with two wings (24 a ,24 b ) diverging in a direction away from the open mouth (25) of the housing.

Inventors: HOLLAND, JOHN ANTHONY
Applicants: VAX APPLIANCES (AUSTRALIA) PTY LIMITED
Application year: 1988
Main classification: A47L7
IPC codes: A47L11, A47L9, A47L7