A SCRUBBING MACHINE

Abstract: A brush set which is particularly useful for cleaning the hull (8) of a ship below the waterline, comprising brush holder means (2), rotary brush means (3) mounted on said brush holder means (2), rotary brush driving means (4), suction means (14) to press said brush means onto a surface (8) to be cleaned, and means (9, 10) to support said brush means (3) on said surface (8) to be cleaned and means adapted to adjust the driving force and suction force.

Description: The invention relates to a scrubbing machine comprising a holder carrying at least one rotary brush in said holder, a drive with an impeller within said holder to rotate said brush(es) on a surface to be scrubbed, spacer means in the form of running means such as rollers or wheels, and a positive pressure line connected to said holder to rotate said drive with said impeller and said brush(es). Such a scrubbing machine is described in US patent specification 4,052,950. Said prior scrubbing machine has said positive pressure line connected to said drive with said impeller to rotate said brush(es) so that scrubbed-off suction material would be sucked through said impeller and discharged in, for example, a net bag, whereby said impeller would be fouled and eventually be clogged by said scrubbed-off material. Moreover, said prior scrubbing machine has the disadvantage that when the brushes under the suction created by the rotating impeller are too strongly oppressed, the brush rotation is largely braked so that their scrubbing action is reduced, and reversely, their oppression and scrubbing action is too slight under a fast brush rotation, and there are no means present to effectively control said interaction when brushing. The aim is to eliminate said disadvantages of the prior scrubbing machine, which according to the present invention is realized by the new provisions that a suction line is connected to said holder to remove scrubbed-off material from said brush(es), with adjustable spacer means in the form of a telescopic holder part of said holder, sliding legs or running means such as rollers or wheels being connected to the scrubbing machine to control brush oppression under the suction force exerted through said suction line so that too heavy a brush oppression onto said surface to be scrubbed resulting in a braking of the brush rotation is prevented. The brush(es) can thus be firmly oppressed, and yet they can be rotated without too strong a braking action so that the brushing action will always be properly effected without any interference. The brush pressure should, of course, be sufficient but too strong an oppression would brake the brush rotation too much for a proper operation. The scrubbing machine known from said US patent specification 4,052,950 has no adjustable spacer means to effectively control the brush action on any occasion. It is thereby preferable to suck about the brush, and thus not through it, so as to avoid that scrubbed-off material would accumulate within the brush, and is rather drawn from it so that the brush is kept clean without any clogging of it, and that it can further properly exert its scrubbing action for a longer stretch of time. To accomplish that a brush sucks itself onto a surface to be scrubbed, it is only required that its rotation field is intersected by said surface so that a centripetal suction force vector normal thereto is created which is especially obtained when a brush has its axis of rotation not strictly normal but inclinedly directed on the surface to be scrubbed or parallel thereto. According to a preferred embodiment of the herein presented scrubbing machine, said positive pressure on said drive is applied through a hydraulic pressure vessel pressurized by a pneumatic pump with pressure limitation. In an alternative embodiment of the herein presented scrubbing machine the measure is taken that said scrubbing machine has a pump connected thereto, the pressure lines as well as the suction lines of which are to be connected to the scrubbing machine so that thereby both pressurizing and suction action takes place through the control line, with a filter being connected upstream of said pump. Additionally it is preferred that said filter comprises a filtrate reservoir, particularly an exchangeable filter bag, in view of environmental protection. When there is sufficient filtrate, that is to say material that is filtered out of the flow medium, accumulated in the bag, the bag is then removed from the line and replaced by an empty bag, and the filtrate is disposed of. A foul collector vessel is known per se from French patent specification 2534584 but that does not comprise a filter bag to be connected to a filter. Furthermore, according to an efficient arrangement a reservoir is connected to said pump which is adapted to continue the control of the pressure line when said pump is switched off by syphon action, with the additional provisions that said reservoir is adapted to be replenished or, in a hydraulic pressure vessel arrangement, to be pressurized by pressurized air, and that said pump is switched off and on, respectively, by a pressure sensor at a predetermined respectively high and low pressure limit for a continuous operation. In a particularly suitable embodiment one central driving unit drives a plurality of brushes mounted about it, and said central driving unit also provides for the drive of running wheels. Thus, in one operation course a very large surface like the shell plating of a large ship can be brushed clean. Running rolls are known per se from US patent specification 4,052,950 indeed, but the adjustability fo the brushes with respect to such running rolls in view of an optimum brushing action is not suggested therein. The invention is further described in the following in view of illustrative embodiments thereof as represented in the drawings. Figure 1 shows a working scheme of the scrubbing machine according to the invention; Figure 2 is a view, in longitudinal section and drawn to a larger scale, of the holder, with the brush and brush drive arranged therein; Figure 3 is a perspective view of an impeller motor functioning as a drive of the brush, and having in cross-section in the onflow direction inclined impeller blades to produce suction force to suck the brush onto a surface to be brushed; Figure 4 schematically shows, in longitudinal section, a drive comprising bevel gears, and a system of brush rolls, each to be rotated about the axis of the system as well as about their own axis so as to self provide the suction force to be sucked onto the surface to be brushed in their action; Figure 5 is a scheme of a pressure reservoir or hydraulic pressure vessel with its pump unit which can also be installed at a distance of the scrubbing machine, for example on deck of a boat in view of underwater brushing the hull of a ship so as to remove algae and other growth from the hull, which view also shows the dual operating line comprising a pressure and a suction line to drive the brush and to suck it onto the surface to be scrubbed and to discharge the brushed-off material; Figure 6 is a cross sectional view, to a larger scale, of the dual operating line of the herein presented scrubbing machine; and Figures 7 and 8 show, in plan view, a brush set mounted on a working platform comprising, as represented, three brushes with alternately arranged therebetween spacer means in the form of running wheels. The scrubbing machine 1, as represented in the drawing, is provided with a holder 2 in which a brush 3 having a drive 4 to rotate the brush 3 is arranged. The rotary brush shaft is indicated at 5. The holder 2 has, as represented, a telescopic part 6 which functions as a spacer means and is longitudinally movable on the casing 7 of the drive 4 as indicated by the twin arrow in Figure 1 and is then, after being placed in the desired position so as to obtain a predetermined brush oppression onto the surface 8 to be brushed, each time to be secured on the casing 7. Around the holder edge 9 a drag seal 10 is provided, by means of which the scrubbing machine 1 will be held onto the surface 8 to be brushed, while producing, in a manner to be further described in more detail, a vacuum pressure within the holder part 6 to such the machine 1 onto the surface 8 to be brushed. Due to the adjustability of the telescopic holder part 6 with respect to the casing 7 with the rotary shaft 5 mounted thereon and the rotary brush 3 seated thereon, the brush hairs project beyond the holder the distance required for a predetermined brush oppression, said drag seal 10 also being well oppressed onto the surface 8 to seal the suction chamber 11 which is formed within the holder part 6. It should be remarked, however, that the oppression of the drag seal 10 and the brush 3 as a matter of fact should not be so strong that the drag seal 10 and the brush 3 would no longer be smoothly movable along the surface 8. In spite of its sealing oppression onto the surface 8, the drag seal should nevertheless allow the scrubbing machine 1 to smoothly move along said surface 8 and the oppression of brush 3 should be a firm oppression indeed to properly brush the surface 8, but should not be such a strong oppression that the brush rotation would be retarded too much. The telescopic positioning of the holder part 6 on the casing 7 should thus be finely adjustable and readily to be effected, for example by means of screwthread with a fine pitch in order to permit proper control of the relative adjustment of the brush 3 and the seal 10. In the working scheme of Figure 1 is represented that the drive 4 is controlled by pressure through the line 12, as indicated with a plus sign, which is supplied by a hydraulic pressure vessel or, in more general terms, by a pressure reservoir 13 to which the pump 14 as represented is connected with its pressure side. The pump 14 is adapted to be connected with its suction side through a suction line 15 to the suction chamber 11 which is formed within the holder 2, as indicated in dotted lines in Figure 1, to produce the required vacuum pressure therein as already stated in the foregoing, and to suck the brushed-off material which is accumulated within the holder 2, therefrom and to discharge this through the suction line 15. Upstream of the pump a filter 16 with its filter reservoir 17 in which brushed-off material can be accumulated, is connected to the suction line 15. The filtrate reservoir 17 preferably comprises a filter bag which is removable from line 15 and which from time to time, when it is filled, can be detached and replaced by an empty bag, so that the filtrated brushed-off material can be disposed of and will not come in the environment. Otherwise the suction for the attachment of the brush 3 to the surface 8 to be brushed can also be produced or enhanced efficiently by a rotary brush which has a rotation force component in the direction of this surface 8, such as the rotary brushes 3 shown in Figure 4, which draw themselves onto the surface 8. This is because the surface 8 intersects a force field, or more correctly termed, cuts it off so as to produce a centripetal force vector drawing the brush 3 and the surface 8 one to another. At this point it is remarked that, although in Figure 1 the spacer means controlling the brush oppression is depicted as a cylinder or sleeve 6 which is telescoped on the casing 7, for spacer means, as a matter of course, also positioning legs, rollers or wheels could be used, such as particularly in a case that no sealed suction chamber needs to be used when the brushes themselves are capable to provide the suction force like the brushes 3 shown in Figure 4. In all cases it is desirable that from the suction chamber 11 no suction is applied through the brush 3, but that the brushed-off material is sucked around it so as not to accumulate in the brush and interfere with its proper action. To that end the brush 3 in Figures 1 and 2 has a closed brush bottom 18 through which no suction can be applied, so that no brushed-off material will be drawn into the brush 3, but that it will be sucked away around the brush 3 for its discharge through the suction line 15 which as indicated by a minus sign will suck on the chamber 11. Figure 2 shows in more detail a view of the brush holder 2 and particularly of the drive 4 mounted therein, which as shown comprises an impeller motor. It is preferred that the impeller 19 has its impeller blades 20 inclined in the onflow direction in cross section so as to apply a suction for the attachment of the brush to the surface 8 to be scrubbed through apertures 21 in the impeller casing 7, which are here only schematically represented, which suction is also here not applied through the brush 3 due to a closed brush bottom plate 18, so as to avoid accumulation of brushed-off material in the brush 3, but has its effect around the brush 3. Figure 3 is a perspective view of such an impeller 19 with inclined impeller blades 20. The impeller 19 could of course also have multiple flights in a staged embodiment in which the impeller casing 7 could also comprise a volute as every impeller pump may have. In Figure 2 for spacing means to maintain the desired brush oppression positioning legs are used whereas in Figure 7 running wheels are used to that end as will be described in more detail hereafter. The drive 4 shown in Figure 4 comprises bevel gears 24 to drive a set of brush rolls 3 which, due to the fact that their rotation force field is normal to the surface 8 to be scrubbed, are capable to provide for their own suction onto said surface 8, as already explained in the foregoing. Figure 5 schematically shows the arrangement of a hydraulic pressure vessel, or more generally termed a pressure reservoir 13, controlling the drive 4 through a pressure line 12 which in its preferred form is embodied as a fall tube for additional dynamic pressure, its pump 14, as described hereabove, preferably having a pump filter 16 with filter reservoir 17 upstream connected thereto in the suction line 15 which is connected to the scrubbing machine 1. Figure 6 shows the dual operating line comprising the pressure line 12 and the suction line 15 in cross section at the location in the line where said two line parts 12 and 15 extend in joined connection as a twin operating hose 25. The unit 12-17 providing pression and suction may be arranged on the deck 26 of a boat when it concerns a large installation designed for scrubbing the hull of a ship underwater, with the hose 25 leading to the scrubbing machine 1 preferably comprising a plurality of brushes 3 as shown in Figure 7 which are mounted on a working platform 27 in an alternating arrangement with running wheels 23 mounted inbetween on said working platform 27, to function as spacer means, and due to which the scrubbing machine 1 can easily be manoeuvred over the surface 8 to be brushed, by a diver who is in charge of the brushing activities. In this case the fluid, driving the machine 1, consists of a liquid such as water. Also a closed oil-hydraulic control circuit could be used, and certainly also a pneumatic circuit using a gas such as air. It is remarked that the wheels 23 may comprise both fixed and castor wheels. The hydraulic pressure vessel can be kept pressurized by a fill pump having its working reach limited by pressure sensors. In the interface which is present in the pressure reservoir, of course also level sensors could be used to limit the working reach of the pump. Finally it is remarked that within the scope of the invention, still further embodiments would be possible. Instead of brushing or scrubbing, cleansing or painting with a controlled dropwise paint supply to the brush can be involved, for example. Figure 8 shows the possibility that one central suction unit 4 would drive a plurality of brushes 3 mounted thereabout on a working platform 27, and that also the drive of the wheels 23 is taken off said suction unit, one of said wheels being represented as a castor or steering wheel. This possibility could most suitably be applied, in a flat embodiment, to brush the bottom of the hull of a ship with the suction unit operating at a small distance below the hull so as to remove and dispose of the growth from the ship in an efficient manner.

Claims: A scrubbing machine comprising a holder carrying at least one rotary brush in said holder, a drive with an impeller within said holder being adapted to rotate said brush(es) on a surface to be scrubbed, spacer means in the form of running means such as rollers or wheels, and a positive pressure line (12) connected to said holder (2) to rotate said drive (4) with said impeller (19) and said brush(es) (3), characterized in that a suction line (15) is connected to said holder (2) to remove scrubbed-off material from said brush(es) (3), with adjustable spacer means in the form of a telescopic holder part (6) of said holder (2), sliding legs (22), or running means such as rollers or wheels (23) being connected to the scrubbing machine (1) to control brush oppression under said suction force. A scrubbing machine (1) according to claim 1, characterized in that said positive pressure (+) on said drive (4) is applied through a hydraulic pressure vessel (13) which is pressurized by a pneumatic pump (14) with pressure limitation. A scrubbing machine (1) according to claim 1 or 2, characterized in that said scrubbing machine has a pump (14) connected thereto, the pressure (+) line as well as the suction (-) line of which are to be connected to the scrubbing machine (1), with a filter (16) being connected upstream of said pump (14). A scrubbing machine (1) according to claim 3, characterized in that said filter (16) comprises a filtrate reservoir (17), particularly an exchangeable filter bag, in view of environmental protection. A scrubbing machine (1) according to claim 3 or 4, characterized in that to said pump (14) a reservoir (13) is connected which is adapted to continue the control of the pressure line (12) when said pump (14) is switched off by syphon action. A scrubbing machine (1) according to claim 5, characterized in that said reservoir (13) is adapted to be replenished or, in a hydraulic pressure vessel arrangement, to be pressurized by pressurized air. A scrubbing machine (1) according to any of claims 4-6, characterized in that said pump (14) is switched off and on, respectively, by a pressure sensor at a predetermined respectively high and low pressure limit. A scrubbing machine (1) according to any of the preceding claims, characterized by one central driving unit (4) driving a plurality of brushes (3) mounted about it. A scrubbing machine (1) according to claim 8, characterized in that said central driving unit (4) also provides for the drive of runnning wheels (23).

Inventors: VAN DER TAK, JOSEPHUS ANTONIUS MARIE
Applicants: VAN DER TAK, JOSEPHUS ANTONIUS MARIE
Application year: 1987
Main classification: B63B59
IPC codes: B63B59