Abstract:
A leaf collection apparatus and method whereby leaves are vacuumed into a collector in a manner to reduce dust spread to the area around the equipment and on the equipment operators. Leaves are discharged by a vacuum device into a collector and retained by screened internal walls. Fine leaf particulate passes through the screens and is directed through the floor to the ground under the collector where the particulate accumulates to facilitate collection. Reusable dust bags may be placed under the floor of the discharge path to collect the particulate matter as it is exhausted through openings in the floor. A fluid spray may be injected into the discharge of the vacuum collection device to wet the leaf particulate and facilitate settling within the collection box.

Description:
FIELD OF INVENTION  
         [0001]    This invention relates to an apparatus and method for vacuum collection of debris, such as leaves. In particular, this invention relates to a collector which maintains cleanliness in the area surrounding the device by controlling the discharge of fine particulate exhaust.  
           [0002]    BACKGROUND OF THE INVENTION  
           [0003]    Heretofore, vacuum leaf collection equipment has been manufactured and known in the art. Traditional designs of vacuum leaf collectors/loaders employ a large-diameter impeller, driven from a large gas or diesel engine. The impeller pulls a large volume of air through a vacuum hose or other attachment used to collect leaves. The leaves that travel through the impeller are reduced in size and broken apart, many pulverized into very small particles. Leaves are exhausted from the leaf collector into a leaf collector box.  
           [0004]    Collector boxes have been designed with enclosed sides and a screened roof. The screened roof retains the leaves within the collector box, but lets air escape through the screening. Due to the large volume of exhausting air, fine leaf particles are also entrained in the air and pass through the screening. These particles go into the atmosphere above the leaf collector box, creating clouds of dust and particles that fall on operators, equipment, and parked cars. Depending on wind conditions, the dust may be carried to surrounding houses and other property in the area. The resulting operation is very dirty, especially if the leaves are dry and brittle. Operators sometimes will wear dust masks, hoods, and eye protection against the dust. None of the related devices have adequately addressed this problem. No invention to date has solved the problem of dirty exhaust from leaf collectors.  
         SUMMARY OF THE INVENTION  
         [0005]    According to the present invention, the foregoing and other objects and advantages are attained. The present invention relates to a vacuum apparatus and method for collecting debris, such as leaves, litter, grass clippings, and other types of yard waste, in a way that minimizes exhaust of fine particulate debris and leaf matter, maintains cleanliness of the area in the vicinity of the operating equipment, and improves the cleanliness condition for the workers who operate the equipment.  
           [0006]    A first general aspect of the invention provides an apparatus for collection of debris comprising a vacuum device; a collector operatively attached to the vacuum device; and a discharge opening positioned on one of a bottom and a side of the collector.  
           [0007]    A second general aspect of the invention provides an apparatus for collection of debris comprising a vacuum device; an airstream for carrying debris from the vacuum device; a tank of fluid; at least one inlet for injecting a fluid from said tank of fluid onto said debris within the airstream; and a collector operatively attached to receive said airstream.  
           [0008]    A third general aspect of the invention provides an apparatus for the collection of leaves and fine leaf particulate comprising a vacuum device for vacuuming said leaves into an airstream; a collector operatively attached to the vacuum device through a discharge chute; a fluid injection system for wetting the leaves and fine leaf particulate within said discharge chute; a filter separating the collector into a first volume and a second volume; two screened walls forming said filter wherein each screened wall is located parallel to and inboard a sidewall of the collector and further each screened wall runs vertically from the floor to the solid roof and horizontally from the forward wall to the rear wall; a lower wall section of solid construction comprising approximately the lower one-third of the screened wall; an upper wall section of screen mesh comprising the upper two-thirds of the screened wall; and a plurality of openings in the floor of the collector beneath the second volume.  
           [0009]    A fourth general aspect of the invention comprises a method for collection of debris comprising partitioning, with a filter, a collector into a first volume and a second volume; vacuuming the debris with a vacuum device into an airstream; discharging the airstream containing the debris into the first volume of the collector; collecting the debris due to gravity and impingement within the first volume of the collector; filtering the debris from the airstream with the filter further causing the debris to collect within the first volume of the collector; and exhausting the filtered air stream through at least one opening in a side or bottom surface of the second volume.  
           [0010]    A fifth general aspect of the invention comprises a method for containing the residual debris of a filtered air stream from a collector comprising locating at least one exhaust path from the collector on least one of the floor or side of the collector to direct said filtered air stream to a particulate collection device for the residual debris; positioning a removably attachable particulate collection device proximate to said exhaust path from the collector; collecting said residual debris in said particulate collection device during intake and collection of said debris; and emptying and replacing said containment device when full with said residual debris.  
           [0011]    A sixth general aspect of the invention further comprises a method for collection of debris comprising vacuuming the debris with a vacuum device into an airstream; storing a fluid in a tank; injecting the fluid from said tank to wet a fine particulate debris within the airstream; discharging said debris into a collector; collecting said debris within said collector; and further collecting said fine particulate debris by gravity and by impingement within said collector.  
           [0012]    These and other aspects, advantages and salient features of the invention will become apparent from the following detailed description, which, when taken in conjunction with the annexed drawings, where like parts are designated by like reference characters throughout the drawings, disclose embodiments of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     Some of the embodiments of this invention will be described in detail, with reference to the following figures, wherein like designations denote like members wherein:  
       [0013]    [0013]FIG. 1 illustrates a side view of an embodiment of a vacuum leaf collection apparatus in accordance with the present invention;  
         [0014]    [0014]FIG. 2 illustrates a top sectional view of an embodiment of the collector in accordance with the present invention;  
         [0015]    [0015]FIG. 3 illustrates a top sectional view at floor level of the collector in accordance with the present invention;  
         [0016]    [0016]FIG. 4 illustrates a side sectional view of the collector showing the screened wall and support members within a collector in accordance with the present invention;  
         [0017]    [0017]FIG. 5 illustrates a side view an alternate embodiment of a vacuum leaf collection apparatus including mounting of a dust collection bag system in the exhaust air discharge path beneath the collector in accordance with the present invention; and  
         [0018]    [0018]FIG. 6 illustrates the mounting of a fluid tank, pump, piping, and spray inlets for injection of a fluid into the discharge of a vacuum device for a leaf collection apparatus in accordance with the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0019]    Although certain embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modification may be made without departing from the scope of the claims. The scope of the present invention will in no way be limited to the number of consulting components, the material thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of an embodiment. Although the drawings are intended to illustrate the present invention, the drawings are not necessarily drawn to scale.  
         [0020]    Referring to FIG. 1, a leaf collection apparatus, hereinafter referred to as  10  is shown, which may include a vacuum device  15 , a discharge device  20 , and a collector  55 . The vacuum device  15  may be an apparatus such as fan, vacuum pump, or large diameter impeller. The vacuum device  15 , the discharge device  20 , and the collector  55  may be mounted on a trailer, such as trailer  45 . The apparatus  10  may also be mounted on a cab and chassis (not shown). Several alternative embodiments may exist whereby the collector  55  may be permanently mounted on its own trailer  45  or may be chassis mounted (not shown).  
         [0021]    The vacuum device  15  may include a large diameter impeller  35  contained within an impeller housing  40 . Rotation of the impeller  35  establishes suction on the intake side of the impeller housing  40 . A suction hose  30  or similar conduit directs debris, such as leaves, collected off the ground by a suction head  25  to the impeller  35 . Any suitable type of drive device, such as a gasoline or diesel engine (not shown), may be coupled to and power the impeller  35 . Debris and leaves are sucked off the ground into an airstream  17  created by the vacuum device  15 . The airstream  17  within the various figures will be represented by double arrows. The debris and leaves within the airstream  17  passing through the impeller housing  40  may be chopped up by action of the impeller  35  thereby creating, in part, small particles of debris, leaf sections and fine particulate of leaf dust. Whole leaves, leaf sections, and leaf dust are discharged from the impeller housing  40  and carried within the airstream  17  through the discharge device  20  comprising many possible chute or tube arrangements to convey the leaves to the collector  55 . One embodiment utilizes a path from the impeller housing  40  through a discharge chute  50 , which is flexible and extended, directly discharging into the collector  55 . A rubber boot-type sealing device  70  or other similar seal prevents leakage of fine leaf particulate to the ambient air outside, at the juncture of the impeller housing  40  and the discharge chute  50 .  
         [0022]    Referring again to FIG. 1, an embodiment of the collector  55  is a rectangular box of steel construction with substantially solid walls. The collector has sides, a top, and a bottom. The sides are defined by both a front and rear, and the two sidewalls. The forward wall  75 , or front, of collector  55 , closest to the vacuum device  15 , is penetrated by the discharge chute  50  to accept leaf discharge. The top surface, or top, of the collector  55  is a solid roof  80  that prevents exhaust of fine leaf particulate to the outside atmosphere above collector  55 . The rear surface, or rear, of the collector  55  is of substantially solid construction, consisting of a hinged rear door  85  pivoting on hinges  90 . Sidewalls  95  and a floor  100 , or bottom, are also of substantially solid construction. Wall support members  105  may be provided to provide structural strength to the forward wall  75 , the hinged rear door  85 , the sidewalls  95 , and the solid roof  80  to contain the debris load or the air pressure that builds up within collector  55 . Floor support members  107  provide support from below for the floor  100  and the overall weight of the collector  55 . The collector  55  may be disposed on the trailer  45  with a dumping mechanism, such as a hydraulic lift, (not shown) that raises and lowers the forward end of collector  55  such that the leaf contents empty, by gravity, through hinged rear door  85 .  
         [0023]    Referring to FIG. 2, which shows a top sectional view of the collector  55 , one alternative embodiment may include a receiving chute  50 . The receiving chute  50  is mounted to the collector  55  such that the exhaust end of the receiver chute  50  penetrates the collector  55 . Again referring to FIG. 2, the internal volume of the collector  55  is divided into a first volume  60  and a second volume  65  by screened walls  115 . The screened walls  115  may comprise various configurations internal to collector  55 . In one embodiment, the screened walls  115  may extend the length of the collector  55  from the forward wall  75  to the hinged rear door  85 . Vertically, the screened walls  115  may extend from the floor  100  to the solid roof  80 . One screened wall  115  may be located inboard of and parallel to each sidewall  95 , separated from the sidewall  95  by the wall support members  105 . The first volume  60  is the main space of collector  55 , bounded by the solid roof  80 , the floor  100 , the forward wall  75 , the hinged rear door  85  and the screened walls  115 . The second volume  65  of the collector  55  includes all of the individual spaces between the screened walls  115  and sidewalls  95  and bounded by the solid roof  80  above, the floor  100  below, and separated from each other by the wall support members  105 .  
         [0024]    Referring to FIG. 3, the floor  100  forms the bottom surface of collector  55  between the screened walls  115 , the forward wall  75 , and the rear hinged door  85 . The floor openings  110  provide a path to exhaust the filtered airstream  17  from the second volume  65  of the collector  55 .  
         [0025]    Referring to FIG. 4, the screened walls  115  may include a lower wall section  120  of substantially solid material construction, such as steel, and an upper wall section  125  that includes a screen mesh  130 . The lower wall section  120  includes approximately one-third of the height of the collector  55  and the upper wall section  125  includes the remaining approximately two-thirds of the height. The screen mesh  130  of upper wall section  125  has openings in the mesh sized to retain large leaf sections within the first volume  60  of the collector  55 , but to allow fine leaf particulate and leaf dust in the airstream  17  to pass through to the second volume  65  without clogging. The lower wall section  120  provides structural strength to the screened wall  115  in order to support the leaves that accumulate in the first volume  60  and also to hold any force that builds up as a result of pressure drop across the screened walls  115 . Wall support members  105  provide backing support for the screen mesh  130 . Depending on the specific opening size of the screen mesh  130 , additional support to the screen mesh  130  may be provided by screen support members  133  operatively attached between wall support members  105 .  
         [0026]    Debris and leaves carried within the airstream  17  exiting from vacuum device  15  pass through discharge device  20  into collector  55 . The larger and heavier pieces of debris and leaves drop to the floor  100  of collector  55  by gravity directly or after colliding with the forward wall  75 , solid roof  80 , hinged rear door  85 , or the screened walls  115  of the collector  55 , losing energy in the collision and then falling to the floor  100 . The screened walls  115  act as a filter, retaining the larger pieces of debris and leaves exhausted from discharge device  20  into collector  55  within the first volume  60 , but permitting some fine debris, fine leaf particulate, and dust within the airstream to pass through to the second volume  65 , along with the airstream  17 . After the airstream  17  passes through the screen mesh  130  of upper wall section  125 , the airstream hits the sidewalls  95  and is forced down to a plurality of floor cutouts  110  in the floor  100  of collector  55 . Fine debris, fine leaf particulate and dust that passes through the floor cutouts  110  exhausts downward below the collector  55 . An alternative arrangement may permit the airstream  17  exhaust from the collector  55  through various openings (not shown) on the sidewalls  95  of the collector  55  or in other portions of the sides of the collector  15 .  
         [0027]    The floor  100  of the collector  55  is substantially solid with structural support provided by a plurality of floor supports members  107  located below. Exhaust paths for leaf particulate and airstream  17  from the second volume  65  are provided through floor cutouts  110  of the floor surface between screened walls  115  and sidewalls  95  and between adjacent floor support members  107 . The airstream  17  entraining fine leaf particulate, exhausting through floor cutouts  110 , is directed downward to the ground directly beneath the collector  55 . Leaf particulate falls towards the ground and thus will tend to collect at the ground location, or immediate vicinity, where it hits or falls rather than rising and going in the atmosphere. Because the leaf particulate is not exhausted through the solid roof  80  to the airspace well above the ground, drift of the leaf particulate is minimized and the amount of dust falling on surrounding areas is limited. Exhaust of the airstream from beneath the collector  55  will also be below the head and face of the operators. Exhaust at a lower height and less drift of particulate also provides a cleaner work environment for the operators and lessens the need for hoods and other protective equipment. The settling of leaf particulate in a relatively limited area under and around the leaf collector apparatus  10  makes it easier for the operators of the equipment to clean the area after leaf collection is complete.  
         [0028]    An alternate embodiment of the invention, as shown in FIG. 5 may further include one or more particulate collection devices mounted beneath the collector  55 . The airstream  17  entraining leaf particulate from second volume  65  of collector  55  is exhausted in a downward direction through floor cutouts  115 . The exhaust air hits the particulate collection devices and the entrained leaf particulate will tend to fall out. The airstream  17  is exhausted from openings in the particulate collection device  134  to the ground below. The particulate collection devices may be removably attached to the collector  55  with bolting, screwing, hanging on hooks and other suitable means to permit removal for emptying or maintenance, and subsequent restoration or replacement. In one embodiment, the particulate collection devices may be dust bags  135 . The airstream  17  passes out of the collection device  134  to the ground below where leaf particulate will further tend to drop out. The collection devices enhance cleanliness by: 1) reducing the leaf particulate drifting surrounding the leaf collecting apparatus, 2) reducing the dust reaching the operators, and 3) minimizing the need for cleanup after leaf collection.  
         [0029]    With a traditional design, (i.e., an impeller driven from engine exhausting large volumes of air) dry leaves create much more dust than do leaves that are wet from rain. However, wet leaves are heavier than dry leaves. Wet leaves are more difficult to vacuum off the ground and put more load on the impeller  35  and the engine (not shown) due to their greater weight. Wet leaves will also stick to the impeller  35  and the inside of the impeller housing  40 . Collection of wet leaves improves the environmental conditions surrounding the leaf loader, but can slow down the collection process. Injecting a fluid into the discharge air and coating the leaves and debris with fluid after they have passed through the impeller  35  results in dust control without loading the impeller  35  and engine (not shown) with the extra weight of wet leaves and without fouling the suction hose  30 .  
         [0030]    Referring to FIG. 6, a further embodiment of the invention may additionally mount a fluid injection apparatus  200  on the leaf collection apparatus  10 . The fluid injection apparatus  200  includes a tank of fluid  220 , a fluid pump  225 , a hose  230 , and at least one inlet  240 . In one embodiment, a plurality of inlets  240  may be operatively attached to the discharge chute  50  with a symmetrical arrangement with respect to the airstream  17  between the impeller housing  40  and the collector  55 . The inlets  240  may be comprised of nozzles, injectors, orifices, or other devices capable of injecting the fluid in the form of a spray that can evenly wet the fine particulate matter entrained in the airstream  17 . The symmetrical arrangement of the inlets  240  around the airstream  17  of discharge device  20  provides for uniform wetting of the fine particulate matter in the airstream  17 .  
         [0031]    The fluid spray from the inlets  240  may be applied to the leaves as they pass through the discharge device  20 . The fluid-coated leaf particles become heavy and tend to drop out more effectively in collector  55 . Any fluid that is sprayable, that will coat the fine debris particulate, and that is environmentally benign may be employed. In one embodiment, inlets  240  are mounted on the discharge chute  50 . The discharge chute  50  is a relatively short, straight, and wide duct, through which the airstream  17  discharged by impeller housing  40  passes quickly. Time for dropout of the leaf particles in the discharge chute  50  is limited and fouling of the discharge chute  50  internal surface is minimized. In a further embodiment, it will also be possible to provide the inlets  240  for fluid spray within the collector  55 . The hose  230  conducts the fluid from the tank of fluid  210  to the fluid pump  220  and from fluid pump  220  to inlets  240 . Fluid spray is initiated during vacuuming operation and secured when the vacuuming is stopped. The invention may use water as an economical, effective, and environmentally benign fluid for the fluid injection apparatus  200 .  
         [0032]    The fluid spray may also be used on leaf collection machines that are exhausting leaves into traditional leaf collection boxes with screened roofs. The fluid injection apparatus  200 , used with the traditional collector, will also improve the working environment around the collector.  
         [0033]    Various modifications and variations of the described apparatus and methods of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific embodiments, outlined above, it should be understood that the invention should not be unduly limited to such specific embodiments. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims.