Abstract:
A method and apparatus for cleaning exterior surfaces, particularly aircraft exteriors, which method and apparatus applies cleaning solution to a soiled surface, scours the surface, squeegees the contaminated solution from the surface and evacuates it through a vacuum manifold for collection and environmentally appropriate disposal. Applicant&#39;s method and apparatus are designed principally to alleviate the problem of toxic run-off and ground water pollution as attends present-day wash-rack or bucket and brush type washing operations. Applicant&#39;s method and apparatus are also beneficial from a convenience standpoint, as an aircraft may be cleaned in any location without the necessity of removing the aircraft to a maintenance facility. Applicant&#39;s method and apparatus are also useful for other exterior surfaces, such as for cleaning skyscraper surfaces.

Description:
CITATION TO PRIOR APPLICATION  
       [0001]     This is a continuation-in-part application in respect of U.S. application Ser. No. 10/434,439, filed 08 May 2003 from which, as applicable, priority is claimed under 35 U.S.C. §120 and under provisions of the Patent Cooperation Treaty. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     A. Field of the Invention  
         [0003]     Applicant&#39;s invention relates to apparatuses and methods for cleaning large, environmentally exposed surfaces and to mitigation of ecological damages from cleaning operations.  
         [0004]     B. Background of the Invention  
         [0005]     As will be apparent from the discussion to follow, Applicant&#39;s invention is directed primarily to the cleaning of aircraft. However, it should be noted that the apparatuses and methods discussed may be equally applicable, although not so direly needed, in other applications, such as the cleaning of building surfaces, non-aircraft vehicles, etc.  
         [0006]     Aircraft must be routinely cleaned to remove accumulated dirt, soot, and other pollutants gathered on skin surfaces during operation. Allowing debris to accumulate adversely affects economy of operation. Contaminants on a aircraft&#39;s skin creates an uneven surface over which air flows more turbulently, thus requiring greater force (and fuel) to propel the aircraft at desired air speed. The significance of this effect is evidenced by a past United Parcel Service television commercial in which the company touted its more frequently that normal plane washing schedule for its resulting savings of millions of gallons of fuel each year. Particularly in the commercial realm, dirty aircraft also present an aesthetics and public image problem.  
         [0007]     A serious problem faces the airline and aircraft maintenance industries in connection with their cleaning operations. The problem arises from the heretofore incompatible needs to minimize pollution of ground surfaces and ground water from the resulting mixtures of removed contaminants and cleaning solutions.  
         [0008]     This problem is real, and not simply the product of theory, or of environmental idealism. Airlines have spent millions of dollars constructing wash racks for their airplanes, only to find that they produce too much contaminant run-off to be permitted to operate. The Environmental Protection Agency (EPA) in the late 1990s actually suspended operation of aircraft wash racks for this reason, at substantial cost to the owners.  
         [0009]     Even if modifications to large, commercial airliner sized wash racks are eventually achieved to adequately address the toxic run-off problems (no solutions have surfaced in the decade since open washing became illegal), the problems remain in association with cleaning aircraft of non-major carriers, such as those of smaller, commuter airlines and private planes. These planes must be cleaned, but in most cases will not likely have access to the wash racks which may have been modified to meet EPA standards, and certainly cannot afford to construct their own acceptable wash racks. Hand washing of a plane, much in the manner of washing a car in one&#39;s front yard, will likely result in EPA fines.  
         [0010]     New apparatuses (not costing millions of dollars) and new methods for cleaning aircraft, and not producing illegal run-off and ground contamination, simply do not exist, yet are desperately needed.  
         [0011]     The gravity of the present situation is revealed by the present practices of a prominent freight airline. Because of their inability to wash their planes in any conventional manner, yet also because of their concern for aesthetics, present practice is for their maintenance contractors to smear liquid car was over the surfaces of the aircraft, allow it to dry, and then hand wipe the dried residue.  
         [0012]     This astoundingly archaic method for “cleaning” an aircraft is not merely inefficient. While no one (the EPA, at least) seems to have yet noticed, the very environmental contamination that was to be avoided through liquid run-off is now occurring (with the addition of the dried car wax) in dry, powder form, as the residue, at least in part, blows from the cleaning area as the wiping takes place. Furthermore, this method of “cleaning” an aircraft is very damaging to aircraft paint. Because the aircraft is not washed, then waxed, this method of smearing liquid wax onto the dirty airplane, and wiping the dried residue away amounts to very nearly wiping sand paper over the painted surfaces—the abrasive dirt is trapped in the wax residue and abrades the surfaces as it is “buffed” away. This same freight airline mentioned before has noted that their paint jobs (costing over $100,000 each) are lasting not more than half of the normal service life expectancy).  
         [0013]     It is needed is a method for cleaning aircraft in particular with a liquid cleaning agent (to provide the necessary damage-preventing lubricant which is absent in a true dry cleaning approach),yet avoid prohibited run-off associated with conventional washing. Also needed is a device which can effectively carry out such cleaning on surfaces that are not planer or smooth (such as aircraft surfaces with rivet lines, etc.).  
         [0014]     This latter point is relevant to the fact that liquid and vacuum cleaning combinations are known. It is believed that some companies, for example, sell floor or even window cleaners which include squeegees associated with a vacuum orifice which is designed to remove soil-laden cleaning fluid from a to-be-cleaned surface. However, experimentation with such concepts in the present form reveals that the use of conventional squeegee blades in any combination with vacuum devices will not work effectively with aircraft with their varying surface textures and contours.  
       SUMMARY OF THE INVENTION  
       [0015]     It is an object of the present invention to provide a novel and unobvious apparatus useful in cleaning soiled, exterior surfaces.  
         [0016]     It is another object of the present invention to provide a novel and unobvious apparatus useful in cleaning soiled, exterior surfaces, which apparatus collects removed contaminants and cleaning solutions for environmentally appropriate disposal.  
         [0017]     It is an object of the present invention to provide a novel and unobvious method for cleaning soiled, exterior surfaces.  
         [0018]     It is another object of the present invention to provide a novel and unobvious method for cleaning soiled, exterior surfaces, which apparatus collects removed contaminants and cleaning solutions for environmentally appropriate disposal.  
         [0019]     It is an object of the present invention to provide a novel and unobvious method for cleaning soiled, aircraft surfaces.  
         [0020]     It is another object of the present invention to provide a novel and unobvious method for cleaning soiled, aircraft surfaces, which apparatus collects removed contaminants and cleaning solutions for environmentally appropriate disposal.  
         [0021]     It is another object of the present invention to provide an apparatus which, by combining a modified squeegee design, cleaning solution application means and a vacuum apparatus, effectively cleans soiled surfaces, particularly exterior aircraft surfaces, without appreciable run-off or remaining residue after use.  
         [0022]     In satisfaction of these and related objectives, Applicant&#39;s present invention provides a method and apparatus for cleaning exterior surfaces, particularly aircraft exteriors, which method and apparatus applies cleaning solution to a soiled surface, provides means for scouring the wetted surface, effectively squeegees the contaminated solution from the surface and evacuates it through a vacuum manifold for collection and environmentally appropriate disposal. The squeegee components of the present design are designed such that they uniquely accommodate the irregular surfaces which are typical of those of aircraft exteriors in riveted and seamed areas.  
         [0023]     Applicant&#39;s method and apparatus are designed, not only to alleviate the problem of toxic run-off and ground water pollution as attends present-day wash-rack or bucket and brush type washing operations, but also to provide speed and efficiency in aircraft cleaning operations. An aircraft may be cleaned in any location without the necessity of removing the aircraft to a maintenance facility. Applicant&#39;s method and apparatus are also useful for other exterior surfaces, such as for cleaning motor vehicle, building, boat, and even skyscraper surfaces.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is a perspective view of one embodiment of a head unit for Applicant&#39;s surface cleaning system, rotated to remove soil-laden cleaning solution through the combined action of the apparatus&#39;s squeegee and vacuum components  
         [0025]      FIG. 2  is a cross sectional view of the squeegee blade assembly portion of the apparatus of  FIG. 1 , shown along Line  2 - 2 .  
         [0026]      FIG. 3  is a side elevational view of the apparatus of  FIG. 1 , in its scouring orientation, and shown in use on a horizontal surface (as in the upper surface of an aircraft wing).  
         [0027]      FIG. 4  is a side elevational view of the apparatus of  FIG. 1 , in its scouring orientation, and shown in use on a vertical surface (as in the side surfaces of an aircraft).  
         [0028]      FIG. 5  is a side elevational view of the apparatus of  FIGS. 1 and 4 , rotated to remove soil-laden cleaning solution through the combined action of the apparatus&#39;s squeegee and vacuum components, the orientation of the apparatus and the direction of movement reflecting the unique capacity of the present system to capture soil-laden cleaning solution as it runs downward along a vertical or near vertical surface (such as the side of an aircraft).  
         [0029]      FIG. 6  is a side elevational view of the apparatus of  FIG. 1 , in its scouring orientation, and shown in use on a vertical surface (as in the side surfaces of an aircraft) as if one is using the device from above the cleaning activity.  
         [0030]      FIG. 7  depicts the apparatus of  FIGS. 1 and 6  rotated to remove soil-laden cleaning solution through the combined action of the apparatus&#39;s squeegee and vacuum components, the orientation of the apparatus and the direction of movement reflecting the capacity of the present system to capture soil-laden cleaning solution by simply pulling the unit across a surface (vertical or horizontal).  
         [0031]      FIG. 6A  is a side elevational view of an alternative, preferred embodiment of the head unit of the present invention which includes a scouring head on the same side of the apparatus as the squeegee and vacuum components, rotated for scouring, as well as a buffing, finish-up pad on the opposite side thereof.  
         [0032]      FIG. 7A  is a side elevational view of the apparatus of  FIG. 6A  rotated or pivoted slightly to effect action by the apparatus&#39; squeegee and vacuum components, without need for rotating the unit about its long axis, as with the prior embodiments.  
         [0033]      FIG. 8  is a side elevational view of the apparatus of  FIG. 6A  rotated about its long axis for use of the buffing, finish-up pad of this embodiment.  
         [0034]      FIG. 8A  is a side elevational view of an alternative embodiment of the present invention, shown with a scouring pad immediately adjacent the apparatus&#39; squeegee and vacuum components, and shown in use in a push-to-clean mode.  
         [0035]      FIG. 8B  is a side elevational view of the alternative embodiment of the present invention of  FIG. 8A , shown rotated on its conduit whereby the scouring pad is closest to the user for a pull-to-clean mode of use.  
         [0036]      FIG. 9A  is a side elevational view of an alternative embodiment of the present invention, shown with a modular scouring positioned distal of the apparatus&#39; squeegee and vacuum components.  
         [0037]      FIG. 9B  is a side elevational view of the alternative embodiment of the present invention of  FIG. 9A , shown rotated on its conduit whereby the scouring pad is closest to the user for a push-to-clean mode of use.  
         [0038]      FIG. 10A  is a side elevational view of an alternative, and the presently preferred embodiment of the head unit of the present invention which includes both a scouring pad and a buffing, fishing-up pad on the same side of the apparatus as the squeegee and vacuum components, rotated in this figure for initial scouring.  
         [0039]      FIG. 10B  is a side elevational view of the apparatus of  FIG. 10A  rotated or pivoted slightly to effect action by the apparatus&#39; squeegee and vacuum components, without need for rotating the unit about its long axis, as with some prior embodiments shown above.  
         [0040]      FIG. 10C  is a side elevational view of the apparatus of  FIG. 10A  further rotated or pivoted slightly vis a vis  FIG. 10B  to effect action by the apparatus&#39; buffing pad without need for rotating the unit about its long axis, as with some prior embodiments shown above.  
         [0041]      FIG. 12  is a cross sectional view of the alternative squeegee blade configuration to that of  FIG. 3 , in which squeegee blades are bolted in-place.  
         [0042]      FIG. 13A  is a top plan view of the supporting components of head unit  10  of the present system, in which view a wet/dry vacuum unit and a fluid repository are visible.  
         [0043]      FIG. 13B  is a plan view of the basic components of the fluid delivery and collection components of the present cleaning system.  
         [0044]      FIG. 14  is a substantially schematic view of the fluid circuit implemented by the present system. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0045]     Applicant&#39;s invention includes an apparatus (hereinafter referred to as a “cleaning system” or simply “system”) which operates through the forced application of cleaning solutions onto surfaces which are to be cleaned and, (optionally) after agitation of the cleaning solutions over the soiled surface, recovery of the cleaning solution/contaminant mixture through action of squeegee-like collection means in association with vacuum or suction orifices.  
         [0046]     Referring in combination to  FIGS. 1, 3 ,  4 ,  5 ,  6 ,  7   6 A,  7 A,  8 ,  8 A,  8 B,  9 A,  9 B,  10 A,  10 B,  10 C, and  11 , the head units  10  of Applicant&#39;s invention are designed to deliver cleaning solution in spray jet form, through spray nozzle(s)  12 . Cleaning solution is delivered to nozzle(s)  12  by way of a conduit network  16  which, in turn, is in sealed fluid communication with a source of pressurized cleaning solution, such as via an aqueous pump  70  which, in turn, draws cleaning solution from a cleaning solution container  80 . Soil-laden cleaning solution, which is collected by head units  10  (as with be described in more detail later), is drawn to, and via action of a wet/dry vacuum unit  60 , eventually delivered to a waste repository  100  for environmentally safe containment, handling and disposal.  
         [0047]     Use of the present cleaning system involves producing a spray of cleaning solution. This is achieved by way of nozzles  12  through actuation of respectively assigned solenoid valve control buttons on a control panel  15  which is positioned for convenient operation by a user.  
         [0048]     Nose plate  18  of head unit  10  defines an interior vacuum manifold  22  which opens at the distal end  24  of the head units  10  as a vacuum orifice  26 . Research indicates that, while other embodiments do still provide many of the benefits described herein, optimal cleaning solution recovery by the system&#39;s vacuum feature is achieved when vacuum orifice  26  occupies no more than approximately one-half of the would-be surface area of the distal end  24  of nose plate  18 , as lies between the hereafter-described squeegees. Such restriction of airflow via the vacuum orifice is believed to accelerate the air flow produced by operation of the wet/dry vacuum unit  60 , to thereby enhance the “suction” of soil-laden cleaning solution.  
         [0049]     Vacuum manifold  22  is configured at its proximal end  28  for sealed communication with a vacuum conduit  30 . Vacuum conduit  30  is connected, directly or indirectly, to wet/dry vacuum unit  60  (shown in  FIGS. 13A and 14 ) which is controlled by actuation buttons placed for convenient operation by a user.  
         [0050]     The heart of the present invention lies in the squeegee arrangement and configuration relative to head unit  10  generally, and vacuum orifice  26  in particular. To facilitate the near complete removal of the soil-laden cleaning solution/contaminant mixture from an aircraft&#39;s skin surfaces and collection through vacuum orifice  26 , a first, serrated squeegee blade  39  and a secondary squeegee blade  40  are affixed on either side of the elongate vacuum orifice  26 .  
         [0051]     The serrated (or “pinked”) squeegee blade  39  has proven to be particularly beneficial in rendering the present system effective in the context of cleaning slightly irregular surfaces, such as those of aircraft.  
         [0052]     The use of conventional, straight blade squeegee blades in place of the present serrated squeegee blade  39  leaves considerable traces of soil-laden cleaning solution, and at best leaves streaks, notwithstanding action of secondary squeegee blade  40 . Serrated squeegee blade  39  has been shown to facilitate a smooth gliding action over the aircraft skin surface, particularly with respect to areas having rivets and other surface irregularities (the same is true of other, non-aircraft surfaces tested). This gliding action, as opposed to the “bumpy” movement experienced without serrated squeegee blade  39  aids in maintaining a consistency of suction force with a resulting consistency of liquid removal through vacuum orifice  26 , as well as maximizing the mechanical wiping effect of the blade. All of this arises from the ability of the serrated margin of serrated squeegee blade  39  to accommodate surface irregularities without substantially deforming the blade to the point of being ineffective in its wiping action adjacent such irregularities, or unduly breaking the “seal” as is required for optimal action of the vacuum orifice  26 .  
         [0053]     The serrations of squeegee blade  39  are to be at its narrow edge as contacts a to-be-cleaned surface (as shown in the drawings). Experimentation reveals that serrations, ridges, etc. which might be positioned along the broad edge of a squeegee blade (not shown in the drawings), and which only substantially contact the surface by distorting the blade through pressure toward the to-be-cleaned surface, are not remotely as effective in this context as those shown for the present invention.  
         [0054]     Referring principally to  FIGS. 1, 3 ,  4 ,  5 ,  6 ,  7   6 A,  7 A,  8 ,  8 A,  8 B,  9 A,  9 B,  10 A,  10 B,  10 C, and  11 , one or another a scrub pad assembly  34  is positioned in the variously depicted positions for agitating or scouring and forcefully removing debris from a skin surface of an aircraft.  
         [0055]     Referring principally to  FIGS. 10A, 10B , and  10 C, the presently preferred embodiment includes scrub pad assembly  34  which is positioned on the same side of the head unit  10  as the squeegees  39  and  40  and vacuum manifold  22 . This permits (as shown in the referenced drawings) the use of both scouring pad assembly  34  and the squeegee and vacuum functions of the unit, without rotating the unit about its long axis as with other depicted embodiments.  
         [0056]     In any preferred embodiment, the actual scouring pad  35  itself is removably attached to a platform surface  33  of head unit  10  through hook and eye (i.e. VELCRO) attachment. This facilitates rapid and convenient change out of pads  35  as they wear or become excessively soiled during a cleaning operation.  
         [0057]     Referring again to  FIGS. 10A, 10B , and  10 C, the presently preferred embodiment further includes a buffing, finish-up pad assembly  50  which is positioned on the same side of the head unit  10  as the squeegees  39  and  40  and vacuum manifold  22 . This permits (as shown in the referenced drawings) the further use of a buffing or finish-up pad  52 , along with both the scouring pad assembly  34 , squeegees  39  and  40  and vacuum functions of the head unit  10 , again, without rotating the unit about its long axis as with other depicted embodiments.  
         [0058]     In any preferred embodiment, the actual buffing pad  52  is removably attached to a platform surface  54  of head unit  10  through hook and eye (i.e. VELCRO) attachment. This facilitates rapid and convenient change out of pads  52  as they wear or become excessively soiled during a cleaning operation.  
         [0059]     Referring principally to  FIGS. 4, 5 ,  6 ,  7 ,  6 A,  7 A,  8 ,  8 A,  8 B,  9 A,  9 B,  10 A,  10 B, and  10 C, the configuration and accessorizing of the head unit  10  is for facilitating its use in cleaning surfaces at the many orientations such as are found on an aircraft. Joint  42  is provided in-line of vacuum conduit  30  for permitting articulation of the conduit  30 , in turn, to permit convenient orientation of the head unit  10  for the most convenient, and comfortable use of the system.  
         [0060]     Also, the distal portion of head unit  10  is detachable at juncture  36  from the remainder thereof whereby the unit, while collecting soil-laden cleaning solution, may be moved away from the user, in a pushing action (as in  FIGS. 5, 8A , and  9 B), or in a pulling action (as in  FIGS. 7, 7A , or  10 B). Note that this reorientation is important for optimal performance when changing the principle direction of use, as serrated squeegee blade  39  should always pass over the surface first, followed by the vacuum orifice  26  and secondary squeegee blade  40 .  
         [0061]     Actual use of Applicant&#39;s system is straight forward. When cleaning a surface above or beside which the head unit  10  approaches, a user first actuates the appropriate control button of control panel  15  to produce a cleaning solution spray through nozzle  14  in order to cover a surface area with cleaning solution. Scrub pad  35  may then be used to scour the surface and dislodge debris. Next, having actuated the vacuum unit  32 , the user moves the system portion with serrated squeegee blade  39  and secondary squeegee blade  40  over the cleaned surface to collect the soil-laden cleaning solution, having head unit  10  configured and moving in a direction whereby serrated squeegee blade  39  passes over the surface first, followed by secondary squeegee blade  40 .  
         [0062]     Finally, the unit is either rotated slightly (as in the preferred mode shown in  FIGS. 10A-10C ), or rotated about its long axis (as for the embodiment shown in  FIGS. 6A, 7A  and  8 ) to effect a final touch-up or buffing in the cleaning operation.  
         [0063]     Referring to  FIGS. 13A, 13B  and  14 , portions of the cleaning system supportive of cleaning head  10  include the previously mentioned wet/dry vacuum unit  60 , fluid pump  70  for delivering cleaning solution to head unit  10 , a cleaning solution container  80 , from which cleaning solution is drawing for delivery via the spray nozzles  12  of head unit  10 , fluid pump  90  which transfers used cleaning solution from the wet/dry vacuum unit  60 , and a waste collection repository  100  to which used cleaning solution is transferred by pump  90  for safe disposal.  
         [0064]     All but minuscule amounts of the contaminated cleaning solution are recovered into the vacuum unit, with negligible environmental exposure to the waste product.  
         [0065]     Cleaning solutions which have proven ideal for use with applicant&#39;s system are those available from Aero Cosmetics, LLC of San Antonio, Tex. under the trademark WASHWAXALL.  
         [0066]     Referring to  FIGS. 6 and 8 , attachment of serrated squeegee blade  39  and secondary squeegee blade  40  can be accomplished in any number of ways, with two examples involving a bolt-on approach ( FIG. 6 ), and a slide-in approach ( FIG. 8 ) being exemplified here.  
         [0067]     Referring to  FIG. 8 , the alternative embodiment depicted here lacks the fitting which, as described above, would allow rotating the distal head portion of head unit  10  at juncture  34 , but may involve an alternative squeegee blade system (not shown in the drawings) which allows reorientation of the blades to change direction of use, in lieu of reorientation of the entire distal head portion.  
         [0068]     Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limited sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the inventions will become apparent to persons skilled in the art upon the reference to the description of the invention. It is, therefore, contemplated that the appended claims will cover such modifications that fall within the scope of the invention.