Abstract:
A method of more effectively disinfecting a surfaces by application of a disinfectant foam that remains in contact with the surface. The invention also includes a portable cleaning machine that provides on-the-go generation of a disinfectant foam that can be applied to a surface so that the foam clings to the surface for an extended period of time sufficient to disinfect the surface. Once the surface is disinfected the machine includes equipment for rinsing the surfaces and vacuuming away any remaining residue.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates generally to cleaning and more specifically to a self-contained portable cleaning machine and an in situ method of cleaning public restroom surfaces.  
         BACKGROUND OF THE INVENTION  
         [0002]    One of the difficulties in cleaning public restrooms and the like is to ensure a kill of all the harmful bacteria and the like that are present on the restroom surfaces. Oftentimes with conventional cleaning devices and methods that spray disinfectants onto the surfaces the bacteria are not completely killed. In the present invention, a cleaning machine turns a disinfectant liquid into a disinfectant foam that is applied to the restroom surfaces by an applicator such as a flow-through brush. It has been found that the application of the disinfectant foam, which is a mixture of air and liquid disinfectant, to a restroom surface provides a more effective in situ disinfecting method than methods that spray liquid disinfectants since the disinfectant foam clings or adheres to the restroom surfaces longer than liquid disinfectants that are sprayed on the walls. The result is the present method using a disinfectant in a foam state can provide for a more effective in situ disinfecting than if the disinfectant was applied in a liquid state because the disinfectant foam provides increased retention time over liquid disinfectants which tend to quickly run down the walls of the restroom.  
         SUMMARY OF THE INVENTION  
         [0003]    The present invention comprises a method of more effectively in situ disinfecting surfaces through application of a disinfectant foam to the surfaces. The invention also includes a self-contained, portable, cleaning machine that provides on-the-go generation of a low-moisture disinfectant foam that when applied to a surface clings to the surface for an extended period of time to effectively disinfect the surface. The increased “clinging time” over a liquid of the same disinfectant ensures that one can more effectively disinfect the surface. Once the surface is disinfected the machine includes equipment for rinsing the surfaces and vacuuming up any residue. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]    [0004]FIG. 1 shows a semi-schematic side view of a self-contained portable, cleaning machine;  
         [0005]    [0005]FIG. 2 shows a semi-schematic view of the self-contained portable, cleaning machine of FIG. 1 in a non operational mode;  
         [0006]    [0006]FIG. 3 shows a semi-schematic view of self-contained portable, cleaning machine of FIG. 1 in a water fill mode; and  
         [0007]    [0007]FIG. 4 shows a semi-schematic view of self-contained portable, cleaning machine of FIG. 1 in a cleaning mode. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0008]    [0008]FIG. 1 shows a semi-schematic view of a self-contained portable, cleaning machine  10  comprising a cart  71  supported by a set of front wheels  72  and a set of rear wheels  73 . A handle  74  extends from cart  71  to permit an operator to move cart  71  from one location to another. An electrical cord  69  extends outward from cart  71  which allows one to power the equipment on cart  71 .  
         [0009]    Cart  71  carries a water pump  37 , a clean water tank  82 , a compressor  83  to provide a source of pressurized air, a tank  80  containing a liquid disinfectant, a waste recovery tank  36  and a mixing tank  35  where the liquid disinfectant is mixed with air to form a lightweight disinfectant foam that can cling to the surfaces to be cleaned. A control panel  81  includes an electrical switch  68  and a multi-port valve  21 . Directing pressurized air from compressor  83  though the liquid disinfectant in the foam mixing tank  35  generates a disinfectant in a foam state. That is the disinfectant is no longer in a liquid state but comprises, small multiple bubbles. The disinfectant can be any of a number of conventional disinfectant solutions that are suitable for disinfecting. Directing air through the disinfectant solution mixes the air with the disinfectant solution which causes the disinfectant solution to foam or froth by forming small bubbles of disinfectant which are applied to the surfaces in bubble or foam form.  
         [0010]    Extending outward from cart  71  is a flexible hose  78  that is partially supported in a coiled condition on hanger  77 . One end of hose  78  connects to foam mixing tank  35  and the other end connects to a foam applicator comprising a flow-through brush  79  having bristles  79   a  extending therefrom. In the application of disinfectant foam to the surface the disinfectant foam, which is generated in foam mixing tank  35  is pumped through hose  78  and into brush  79 . As the operator moves the bristles  79   a  along a wall  9  it provides a layer of foam disinfectant  11  which clings to the wall surface. The use of a flow-through brush to apply the disinfectant foam allows for more of the disinfectant foam to be retained on the walls since the splatter from spraying with high pressure wands is eliminated. Thus, the present invention not only provides for a longer “clinging time” of the disinfectant by providing the disinfectant in a foam state rather than in a liquid state but the amount of disinfectant that remains on the surface is increased since the splatter associated with jets of high pressure liquid disinfectant applicators is eliminated. In addition, the disinfectant foam can be sprayed on a surface with less splatter than disinfectant in liquid form since the air bubbles provide are compressible to absorb the impact whereas the liquid in spray form is incompressible which tends to cause the liquid to be reflected from the surface.  
         [0011]    Locate on the back of cart  71  is a second hanger  76  containing a second flexible hose that connects to the vacuum recover tank  37  which can connect to a vacuum squeegee (not shown) to allow a person to vacuum the foam residue from the wall surface  9 . Self-contained portable, cleaning machine also contains a hose  58  (see FIG. 2) that connects to the clean water tank  36  and pump  51  to allow a person to rinse the surface  11 . If desired a conventional spray nozzle can be connected to hose  58  to allow one to spray clean rinse water on the surfaces to be rinsed.  
         [0012]    In order to appreciate the operation of the self-contained portable, cleaning machine reference should be made to semi-schemattic views of FIGS.  2 - 4 . FIG. 2 shows a semi-schematic view of the vacuum recovery tank  37 , the clean water tank  36  the foam mixing tank  35 , pump  51  and a multi-port switch  21  in non-operational mode and FIGS.  3  and FIG. 4 show the self-contained portable, cleaning machine in different operational modes.  
         [0013]    Referring to FIG. 2 the multi-port switch  21  is shown with valves  22 ,  23 ,  24  and  25  in the closed condition. A safety switch is located proximate switch  21  to allow an operator to quickly deactivate the system in the case of an emergency. FIG. 2 illustrates the self-contained portable, cleaning machine in the off mode which allows the self contained portable cleaning machine  70  to be taken from one location to another.  
         [0014]    Entering one side of multi-port switch  21  is a clean water inlet line  44  that fluidly connects with valve  25  and a branch clean water line  45  that fluidly connects with valve  24 . A third line  30  fluidly connects to the source of disinfectant fluid or foam making solution located in tank  80  to direct disinfectant fluid into valve  23 . In the closed condition valves  23 ,  24  and  25  prevent fluid from flowing from left to right through multi-port valve  21 . The top valve  22  controls the flow of liquids and solids into vacuum recovery tank  37 . In the closed condition valve  22  as illustrated in FIG. 2 valve  22  prevents material and solids from flowing through fluid line  56  and into vacuum recovery tank  37 .  
         [0015]    Referring to FIG. 3 the system is shown in a clean water fill mode. In the fill mode valve  25  is open allowing clean water to flow-through line  44  and valve  25  and into the clean water tank  36  which is carried by cart  71 . This provides a source of water that allows the self-contained portable, cleaning machine to be used in areas where a hookup for clean water may not be readily available. The top of clean water tank  36  includes a vent  40  to allow air to escape as one fills the clean water tank  36 . Connected to the lower end of clean water tank  36  is a water pump  51  that has an inlet line  49  and an outlet line  58 . A bypass valve  52  also connects to line  58  and a bypass line  50  extends from bypass valve  52  to clean water tank  36  to allow water to return to the clean water tank  36 .  
         [0016]    If pump  51  is in the on mode water from clean water tank  36  is directed through line  58  to a conventional water spray nozzle (not shown) for rinsing the surfaces with clean water. Thus system  10  can be set in a rinse mode to allow for rinsing of the surfaces with clean water by activating water pump  51  through a switch  68  on control panel  81 .  
         [0017]    Referring to FIG. 4 the self-contained portable, cleaning machine  10  is shown in an operational mode. In the operational mode illustrated in FIG. 4 the valve  25  for supplying clean water to clean water tank  36  is in the closed condition. The valves  23  which allows a foam making disinfectant solution to flow-through line  30  and into a mixer valve  32 . Mixer valve  32  allows one to control the ratio of disinfectant to water that enters line  33  by limiting the amount of disinfectant solution flowing through mixer valve  32 . Similarly, valve  24  is shown in an open condition which allows water to flow-through line  45  and valve  24  where the disinfectant foam and water flow combine and flow-through line  33  into the foam mixing tank  35 . Foam mixing tank  35  contains an air inlet  61  that connects to an air compressor  83  that can supply pressurized air to foam mixing tank  35 . A set of check valves  53  and  54  prevent the contents of tank  35  from flowing backward into compressor  83 . Extending outward from the top of foam mixing tank  35  is a fluid line  41  having a control valve  63  for opening or closing the fluid line  62 . Fluid line  62  connects to flexible hose  78  to direct disinfectant foam under pressure to the flow-through brush head  79 . Activating compressor  83  forces air into the disinfectant solution in foam mixing tank causing the disinfectant solution to form into a froth of bubbles and foam. Consequently, when valve  63  is opened the disinfectant foam flows through valve  63  and fluid line  41  to the flow-through brush applicator  79 .  
         [0018]    [0018]FIG. 4 shows vacuum recovery tank  37  having a vacuum pump  38  with tank  39  including an air vent  39 . When the vacuum pump  38  is in the on condition the vacuum pump can be used as a blower, that is a hose can be connected to air discharge port (not shown) of the vacuum pump  38  to allow a person to blow the vacuum pump discharge air onto the cleaned surfaces to assist in drying the cleaned surfaces. Vacuum pump  38  is also usable in the vacuum mode to allow liquids to be drawn into vacuum recovery tank  37  by connecting a vacuum pick up hose to inlet  39 . With valve  22  in the open condition as shown in FIG. 4 the vacuum pump  38  can be used to empty the foam mixing tank  35  after the task is completed.  
         [0019]    In order to generate foam in foam mixing tank air compressor  83  is activated to direct pressurized air through one way check valves  53  and  54  and into foam mixing tank  37 . The stream of pressurized air is directed into the disinfectant solution thereby generating a foam of disinfectant and water. The foam of disinfectant and water obtained by mixing the air with the disinfectant solution can then be directed onto the surfaces to be cleaned. With the disinfect and water in a foam condition the foam clings or adheres to even vertical surfaces thereby maintaining the disinfectant foam in contact with the surfaces long enough to kill the bacteria present. The increase in “clinging time” provides for longer contact between the disinfectant and the bacteria thereby ensuring a more effective bacteria kill than with a liquid disinfectant that runs off immediately after application. That is, the use of liquid disinfectants that are applied by mists or sprays tend have a shorter “clinging time” as liquid quickly run down the walls and consequently prevents effective bacteria kill.  
         [0020]    [0020]FIG. 4 shows that excess foam can be removed from foam mixing tank  35  thorough fluid line  55  which is coupled to foam mixing tank  35  by a quick-connect coupler  55   a . A further feature of the self cleaning machine  70  is that the machine can be used as a vacuum to remove excess materials and water. To use system as a vacuum system the quick disconnect  55   a  is removed from mixing tank  35  and connected to a flexible hose having a vacuum pick up head attached thereto which allows one to vacuum up excess materials in a manner that one vacuums his or her home.  
         [0021]    In order to have access to various tools as well as to other equipment usable with the present invention a toolbox  89  is also carried by cart  70  and is illustrated in FIG. 1.  
         [0022]    In summary the presenting invention comprises a method of cleaning a restroom comprising the steps of: 1. directing a mixture of water and a disinfectant in a foam condition onto a restroom surface; 2. allowing the foam to cling to the surface for sufficient time to kill the bacteria; and 3. rinsing the surface to remove the foam. In addition, one also can vacuum the surfaces to remove any removing residue on the surfaces and one can also air dry the surfaces with a stream of air.  
         [0023]    In the method shown the foam is applied through a flow-through brush having a plurality of bristles projection therefrom however, it is envisioned other device for applying disinfectant foam could be used that would deliver the foam in a condition where the foam can adhere to the surfaces. By providing for on-the-go generation of foam one can readily generate and apply foam in a continuous application. In addition the strength of the disinfectant foam needs to be changed the ratio of water to disinfectant supplied to the foam mixing tank can be varied to control the disinfectant content of a foam generated from the water and disinfectant. The amount of time the disinfectant needs to remain on the surface varies but the present invention allows the foam to cling to a vertical wall surfaces for a minute or more.  
         [0024]    It should be understood that while reference to bacteria is used herein the type of killing action depends on the disinfectant selected as some disinfectant are effective not only against bacteria but against various spores and the like and are equally suitable for use in the present invention.