Patent Publication Number: US-7909274-B2

Title: Device to reduce clogging of gutters

Description:
BACKGROUND OF THE INVENTION 
     Many residential homes and other buildings are fitted with rain gutters. Rain gutters divert rain water flowing off the roof to a downspout, and thus prevent rain water from dripping off the eaves directly onto the ground. Without gutters, accumulated rain water will fall along a line directly under the eave. This can form an unsightly drip line under the eave, and may damage a lawn or other plantings next to the house. Rain gutters also prevent rain water from falling from the roof onto persons entering or leaving the house. 
     An age-old problem with rain gutters is blockage due to leaves and other debris. This problem is particularly acute in the fall, when leaves which have fallen on rooftops are washed down by rainfall into the gutters and are carried from there to the mouth of the downspout. Wet leaves easily stick together and can accumulate at the mouth of the downspout, clogging the downspout and causing water to back up into the gutter and overflow. 
     For such reasons, gutters must periodically be cleaned of debris, particularly in the area near the downspout connection. This usually involves climbing a ladder and using tools and/or pressurized water to remove manually the compacted organic matter. Aside from the inconvenience involved, there is the danger of falling while handling tools or a hose at the top of a ladder, and the possibility that a gutter may be damaged by the weight of the ladder and the person on it. The risk of falling is particularly troubling in the case of multi-story buildings, where a fall could cause serious injury. 
     One known way to try to reduce clogging in gutters is covering the gutter with a protective screen. Such technique, however, is not entirely effective. Wet leaves which are washed off the roof can stick to the protective screen, blocking the screen openings. When this happens, rain water cannot flow into the gutter, thus defeating the purpose of having a gutter. 
     Albrecht U.S. Pat. No. 3,638,369 discloses a device for clearing a gutter downspout. An auger device is located in the gutter, above the downspout, such that the auger screw extends a short distance down into the downspout. The shaft of the auger screw is connected to an impeller, located above the gutter, such that when the wind blows, the impeller rotates the screw shaft, and the rotating screw in turn forces downwardly any solid matter with which it is in contact. 
     Albrecht only works while the wind is blowing. If it is raining, and there is insufficient wind to rotate the screw, water-soaked leaves and other sticky debris may accumulate at the downspout inlet, clogging the downspout inlet. The auger screw, in fact, makes a blockage more likely, both because the screw partially blocks the downspout opening, and because the screw surfaces are substantially perpendicular to the direction of flow, and thus likely to attract the wet, sticky leaves. 
     If waterlogged organic matter does accumulate around the screw, when the wind again starts to blow it will be harder to start the screw rotating, particularly if it has stopped raining and the matter has partially dried out and hardened. Thus, the auger may become stuck and need to be manually cleaned before it will work again. 
     In Albrecht, even when the auger is operational, leaves and other debris may clog the downspout at its lower end, because the auger pushes the organic mass downwardly generally intact. The auger may actually exacerbate the tendency to clog, insofar as the screw compacts the organic mass while extruding it through the downspout inlet. 
     There is a need for a more effective system for keeping gutters clear. There is also a need for such a system which does not require climbing ladders and, preferably, other human intervention. 
     BRIEF SUMMARY OF THE INVENTION 
     A device for reducing clogging of a gutter comprises a housing which fits in a gutter over the downspout. The device contains a motor-driven grinder mechanism which grinds up waterborne debris passing through the housing, preferably as it exits through the bottom of the housing to the downspout. Preferably, the device also includes a plunger mechanism which helps push water and debris in the housing through the grinder mechanism. Also, preferable the device includes a water sensor and a debris sensor for operating the motor only when both water and debris are present. 
     For a better understanding of the invention, reference is made to the following detailed description of the preferred embodiments of the invention, taken in conjunction with the drawings accompanying the application. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic drawing of an embodiment of a device according to the present invention; 
         FIG. 2  is a block diagram of the device of  FIG. 1 ; 
         FIG. 3  is a schematic drawing of an alternative grinding mechanism for use in the present invention; and 
         FIG. 4  is a top, schematic view of another grinding mechanism for use in the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a portion of a conventional eaves gutter  10 . The gutter  10  has a channel  12  which is normally generally U-shaped or semi-circular in cross-section, and an end wall  14 . It also has a hole  15  for receiving the upper end of a downspout  16  so that rainwater in the gutter  10  flows from the gutter into the downspout  16 . 
     The device according to the present invention includes a housing  20  having a lower portion  22  designed to fit within a conventional gutter  10 , i.e., being generally arcuate cross-section. In the embodiment shown, one end  24  of the housing  20  is open so as to communicate with the channel  12  and allow water and debris present in the gutter  10  to flow into the housing  20 . The other end  26  of the housing is preferably closed. 
     The bottom of the lower portion  22  of the housing  20  includes an outlet  28  located such that, when the housing  20  is placed in the gutter  10 , outlet  28  communicates with the inlet of the downspout  16 , as shown. The outlet  28  may be at the bottom of a vertically oriented tubular wall section  30  which fits snugly inside the downspout  16 . The wall section  30  helps seat the housing at the proper angle, secures the housing  20  against movement, and provides leak-free communication between the housing  20  and the downspout  16 . 
     The device contains a grinding mechanism  32  which is preferably located near the outlet  28  of the housing  20 . In the embodiment of  FIG. 1 , the grinding mechanism  32  is in the form of one or more rotatable blades  34 . A screen or grid  36  may be located between the blades  34  and outlet  28 . The screen or grid  36  may be used to prevent large particles of leaves or other debris from entering the downspout  16  until they have been sufficiently ground up by the blades  34 . The blades  34  may also rub against the screen or grid  36  to help grind up particles. 
     The blades  34  are secured on a drive shaft  38 , which is received in a motor housing  40 . The motor housing  40  contains an electric motor and, if desired, appropriate gearing for driving the shaft  38  at a speed effective to grind up leaves and other debris that may fall into the gutter  10  and be carried into the housing  20 . The motor is connected to any suitable power source, for example a battery  42  which may be charged by a solar panel  44 . Solar-powered battery charging systems are well known and need not be described here. Alternately, the motor may be powered by a conventional house current power line or other power source. 
     Operation of the motor may be controlled manually, i.e., turned on while it is raining. Preferably, however, operation of the motor is automatically controlled, and turned on only when detectors sense the presence of waterborne debris. In the embodiment of  FIGS. 1-2 , a water detector  50  is disposed inside the housing either in or on the bottom surface. Water detectors are well known devices, e.g., are commonly used in connection with sump pumps, and need not be described further here. The presence of debris in the water may be sensed using an electric eye and detector  52  mounted in or on the side of the lower portion  22 . If the electric eye and detector  52  are one unit, a mirror is placed on an opposite wall of the housing to reflect back the signal, which will be partially blocked when debris is present. Also, electric eye systems are well known and used for various applications. 
     According to another aspect of the preferred embodiment, the housing  20  contains a plunger mechanism comprising a piston  60  coupled to a piston rod  62 . The upper end of the piston rod  62  is received in the motor housing  40  and moved vertically up and down, as shown by arrow  64 , so that the piston acts to push water and debris towards the grinder mechanism  32 . In order to allow the piston  60  to move up and down free of the rotating drive shaft  38 , a hole is provided through the piston, through which the drive shaft  38  passes. 
     Any suitable drive mechanism may be used to reciprocate the piston  62 . For example, the piston may be driven off the same motor that rotates the shaft  38 , using a connecting linkage such as a crank and slider (as indicated in  FIG. 2 ) or a cam mechanism, along with appropriate plastic gears. Alternately, the shaft  62  may be driven by a separate motor/linkage or a servo. Mechanisms for driving a shaft in translation are well known and need not be described further here. Moreover, the mechanism for moving the piston  60  need not be a fixed shaft. Any other suitable drive mechanism, such as a flexible drive shaft, spring mechanism, or solenoid, may be employed. 
     Referring to  FIG. 2 , the water sensor  50  and associated electronics act as a normally open switch, which prevents the motor (and separate drive for the plunger, if present) from operating unless water is present inside the housing  20 . The electric eye system  52  and associated electronics act as a normally open switch which prevents the motor from operating unless the beam from the electric eye system  52  is blocked or partially blocked, which will occur if debris is present in the water. In such a manner, the motor will not run unless it is raining and also there is debris inside of the housing  20 . 
       FIG. 3  shows an alternative embodiment of a grinding mechanism. A housing frame  70 , which is open at its top and bottom ends, secures a grid of blades  72  and optional cross-blades  72   a , whose sharp edges face upwardly in  FIG. 3 . The cross-blades  72   a  are preferably perpendicular to the blades  72 , but other angles may be employed. A plunger  74  is positioned above the blades  72 ,  72   a , and is reciprocated by connecting its plunger rod  76  to a motor (not shown). The frame  70  is positioned so that water and debris from the gutter must pass through the grid of blades; the plunger  74  helps push the debris through the grid of blades, thereby grinding or shredding the debris. As used herein, the term “grinding” refers broadly to any process of reducing the size of the solid matter in the debris, including grinding, shredding, and the like. 
       FIG. 4  shows another alternative embodiment of a grinding mechanism. A shaft  80  includes a plurality of helical blades  82 ,  82   a , which are mounted by struts  83  on the shaft for rotation therewith (i.e., similar to a reel-type lawn motor). One end of the shaft  80  is coupled to a motor  84  for rotating the shaft  80  and thereby the blades  82 ,  82   a . The blades  82 ,  82   a  are positioned in a half-cylinder shaped mesh grid  86 , such that the blade edges are close to, or in contact with, the grid surface. The mesh grid  86  is positioned in the path of the flowing water and debris. Thus, as debris flows through the mesh grid  86 , it is ground up by the rotating blades  82 ,  82   a.    
     The foregoing represent preferred embodiments of the invention. Variations and modifications will be apparent to persons skilled in the art, without departing from the inventive concepts disclosed herein. For example, while the example of the grinding mechanism employs rotating blades, optionally in conjunction with a screen or grate, any suitable grinding mechanism may be used. It may be desirable to use a miniaturized version of a kitchen garbage disposal unit, insofar as such devices are especially designed to grind up solids in the presence of water. 
     Alternatively, rather than using rotating blades  34  and a stationary grate, the opposite can be used. By way of example, the grate  36  may be provided with sharp projections, similar to a cheese grater, and a grinding plate may be secured to the bottom end of the rotating shaft  38 . In this manner, the rotating plate grinds the debris into the cutting edges of the grate. 
     As another alternative, the grinder mechanism may be a plurality of parallel blades which are reciprocated in an axial direction, out of phase with one another. The cutting edges of the blades, which may be serrated, face upwardly so that the oppositely moving blades grind up the organic matter as it passes through the blade grid. 
     In addition, the end  24  of the housing  20  which communicates with the gutter channel  12  need not be completely open, or may communicate with the gutter channel  12  in some other way. The opposite end  14  of the housing  20  need not be closed, because the end wall  14  of the gutter  10  will largely prevent water from escaping anyway. 
     Also, while in the exemplary embodiment the grinding mechanism is positioned within a tubular section  30  leading to the outlet  28 , it is only necessary that the grinding mechanism be positioned in the housing so that a substantial amount of the waterborne debris passes through the grinding mechanism prior to exiting to the downspout. Most preferably, however, the grinding mechanism is located in or near the outlet  28 , i.e., within the section  30 , or directly above or below section  30 , so as to use gravity to help feed in the water-borne debris. Also, while in the exemplary embodiment the downspout is shown as directly connected to the gutter, such is a schematic representation only, insofar as it is well known that in practice there is normally an intervening connector. All such modifications and variations are intended to be within the scope of the invention, as defined in the following claims.