Abstract:
The present invention is an enclosed rain gutter for draining water from the surface of a sloped roof and conducting it to a downspout. The invention rain gutter includes a channel that is covered by a mounting flange suitable for insertion under the material covering the roof of a building and a collecting flange connected to the mounting flange by a rounded edge. The collecting flange has openings for delivering water into the channel and features for delivering water to the openings. While the collecting flange features and openings deliver water into the channel, they also exclude debris from entering the channel and in particular they exclude debris might obstruct a downspout.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. Non-Provisional application Ser. No. 09/839,673 filed Apr. 21, 2001 now U.S. Pat No. 6,536,165, which was a continuation in part of U.S. Non-Provisional application Ser. No. 09/776,032 filed Feb. 2, 2001. 
     This application claims the benefit of U.S. Provisional Patent Application No. 60/180,367 filed Feb. 4, 2000, U.S. Provisional Patent Application No. 60/199,681 filed Apr. 21, 2000 and U.S. Provisional Patent Application No. 60/229,717 filed Aug. 31, 2000. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a rain gutter and in particular to an enclosed rain gutter that collects water and rejects debris. The rain gutter of the present invention collects rain water flowing from a roof structure and conducts it to a downspout. The invention rain gutter includes a channel that is covered by a collecting surface. The collecting surface has openings that divert water into the channel by using the property of water that causes it to adhere to a surface. While the collecting surface openings divert water into the channel, they also exclude debris from entering the channel and in particular they exclude debris that would be large enough to obstruct a downspout. 
     BACKGROUND OF THE INVENTION 
     Any home owner whose home is located near vegetation knows the frustration of obstructed rain gutters. Removing debris from rain gutters is a time consuming, difficult and often dangerous task. The prior art describes numerous attempts to provide a rain gutter that will not collect debris and become obstructed. Various types of screens and coverings have been marketed for preventing leaves from collecting in rain gutters. Many of these screens or meshes, when placed over conventional rain gutters only serve to provide another even more unsightly means for trapping and collecting debris such as leaves and twigs. 
     Common prior art rain gutters become obstructed because they are open to falling debris and because the flow of water down the length of the gutter is not managed or controlled. Common prior art rain gutters of the type having a generally flat bottomed, constant and open cross section are an obvious but flawed solution to a problem that seems deceptively simple. A rain gutter need only to perform two functions: 1. collect rain water, and, 2. convey collected rain water to a downspout. A prior art rain gutter is generally flat and open at the top and has an area for collecting water that is many times greater than the actual area of any stream of water that could exit the gutter via a downspout. A prior art rain gutter would overflow long before the cross sectional area of the flow of water into the gutter reached even a small fraction of the total collecting area available. While the vastly oversized, open collecting area of a prior art rain gutter can collect water flowing off of a roof, it is even more effective as a collector of dead leaves and other debris. Most debris falls into the prior art gutter during dry conditions and then is trapped in place during a rain storm when the debris obstructs a downspout. Once a prior art gutter is obstructed, it collects water, overflows and allows adjacent building structures to be water damaged. Prior art rain gutters can also collect snow that after thaw and freeze cycles can accumulate as ice. Moreover, sheets of Ice that form on a sloped roof can slide down into a prior art rain gutter and damage or destroy the gutter. 
     SUMMARY OF THE INVENTION 
     An objective of the present invention is to provide a rain gutter that will collect rain water while not collecting any debris that could obstruct water from entering the gutter or obstruct a downspout so that water can not flow out of the gutter. Another objective of the present invention is to provide a rain gutter that is not open to falling debris or snow. Yet another objective of the present invention is to provide a rain gutter that is not open to sheets of ice or other objects that my slide down a roof. Still another objective of the present invention is to provide a rain gutter having a channel that will carry a large flow of water at a relatively constant velocity along its length over a wide range of drainage load conditions so that any small debris that enters the channel is washed away as water is conveyed to a downspout. 
     The invention rain gutter is designed to be mounted at the lower edge of a sloped, roof of a building adjacent to a vertical surface under the lower edge of the roof. The rain gutter can be fashioned from a continuous sheet of metal. It includes a channel for conveying water to a downspout and a collecting flange for collecting water and diverting it into the channel. Preferably, the channel has a circular cross section that is large enough and extensive enough to carry a substantial flow of water to a downspout. The inside wall of the channel can be mounted to a vertical surface under the edge of the roof or to an eaves under the roof. The collecting flange extends from the outside wall of the channel and over the channel. Preferably, the collecting flange is integral with the outside wall of the channel. The collecting flange can completely cover the channel and can even extend past the inside wall of the channel. The collecting flange can be inserted under the bottom edge of any material covering the roof. Yet, the collecting flange could also be envisioned as a separate cover that can be added to an existing rain gutter. 
     As rain water flows down from the roof, it encounters the collecting flange and begins to flow as a thin sheet that adheres to the collecting flange surface. The collecting flange has a generally hydrophilic surface and has a pattern of openings that conduct the flow of water into the channel. These openings are sized and arranged to exploit the physical properties of flowing water so that the water is conducted into the channel while all but the smallest debris is not conducted into the channel. One possible pattern of openings includes a pattern of openings having diagonal edges situated above a pattern of collecting slots that are located under gaps between the lower ends of the openings having diagonal edges. The openings having diagonal edges have upper edges that are preferably oriented at an angle of not substantially more than 45° with respect to the direction of the flow of water. When the film of flowing water encounters the diagonal edges, it divides and follows each of the upper edges without flowing into the openings. The water flowing along each diagonal edge of each opening forms into a small, fast moving stream. The collecting slots situated under the gaps between the lower ends of the openings include inwardly turned collecting tabs that divert the small streams of water into the gutter channel. The openings having diagonal edges described above may also be replaced by zones on the surface the collecting flange that are non-hydrophilic, that is zones that have a surface that repels water. Another arrangement of openings does not include collecting slots. With this arrangement, diagonal openings have upper edge that change direction so that the upper edge of the diagonal opening defines a “V” shaped angle at the lower end of the diagonal opening. With this second alternative arrangement, a small, fast moving stream of water is unable to adhere to the collecting flange surface where the upper edge changes direction and will therefore separate from the surface of the collecting flange and discharge down through the lower end of the diagonal opening into the rain gutter channel. Yet another example arrangement of openings includes a series of overlapping obtuse triangles having inwardly bent triangular collecting tabs. Because the lower edge of an inwardly bent collecting tab of this arrangement is slightly angled in relation to the descending contour of the surface, a transverse flow is set up on the inwardly bent tab so that water flowing around an adjacent opening is induced into flowing onto the tab and into the channel. A flowing sheet of water will move along an edge even if that edge is oriented at only a slight angle that is not normal with respect to the contour and the direction of the flow of water. 
     In addition to the alternative arrangements of openings and non-hydrophilic zones as described above, the collecting flange itself can be alternately further formed to define a small radius folded edge so that it has an upper portion which is secured to the roof of the building and might be called a mounting flange and a lower portion which performs the water collecting function would still be called a collecting flange. With this alternate configuration, the upper portion or mounting flange extends parallel with the slope of the roof, while the lower portion or collecting flange curves inwardly toward the building and then outwardly away from the building toward the outside wall of the channel. Between the upper portion or mounting flange and the lower, collecting flange is a folded edge that has a radius substantially less than one half inch and that preferably has a radius of about 0.10 inch. The various openings and non-hydrophilic zones described above can be positioned in the lower, inwardly curved collecting flange and are positioned so that the portions of the openings where water is collected into the channel are located on the portion of the curved collecting flange that is sloping back toward the outside wall of the channel. With this configuration, a sheet of flowing water accelerates around the curved collecting flange and pulls the flowing sheet of water around the small radius folded edge while any debris is unable to follow the torturous path around the folded edge and is ejected from the system. 
     With any of the above described arrangements, it is important that any portion of the gutter where water is being diverted into the channel have a surface that is generally hydrophilic. Highly water repellent surfaces would be unsuitable because a flowing sheet of water would separate from such a surface. The inventor has found that thin gauge aluminum having a non-glossy PVC coating provides a suitable surface for the mounting flanges and collecting flanges described above. However, any similarly hydrophilic surface would be suitable for these applications. 
     With the above described arrangements, dead leaves and other debris do not follow the surface tension induced flow of the water and are pushed over the edge of mounting flange or collecting flange. When the portion of the collecting flange having diagonal openings or collecting slots is inwardly curved, then even small articles of air born materials can not settle into the openings. If the rain gutter channel has a circular cross section, if the circular cross section of the channel is properly adjusted and if the channel is properly sloped toward a downspout, the velocity of flow in the channel, at various volume flow rates would be substantially constant so that even very small debris that might enter the channel would be washed out even at low volume flow rates. A channel having a circular shape has the added advantage of not covering a surface to which it is mounted. A flat sided channel will lay flat against an eaves surface to which it is mounted and allow moisture to attack that surface. A circular channel will allow air to circulate between the channel any surface to which it is mounted. 
     Accordingly, the rain gutter of the present invention provides a way to collect rain water from a roof structure without collecting debris that can obstruct the gutter system. The invention rain gutter does not collect debris that can obstruct downspouts. Because even the small amount of small debris that enters an invention rain gutter is washed out even at relatively low volume flow rates, the accumulation of debris that plagues prior art rain gutters does not occur. The invention rain gutter collects rain water while rejecting virtually all debris and therefore can function at an optimum level of performance for a very long period of time without any need for maintenance or cleaning. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention and its many attendant objects and advantages will become better understood upon reading the following description of the preferred embodiment in conjunction with the following drawings, wherein: 
     FIG. 1 is a perspective view of a first embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 1A is a cross sectional view of the first embodiment of the invention rain gutter. 
     FlG.  1 B is a plan view of part of the surface of the first embodiment of the invention rain gutter. 
     FIG. 2 is a perspective view of a second embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 2A is a plan view of part of the surface of the second embodiment of the invention rain gutter. 
     FIG. 3 is a perspective view of a third embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 3A is a cross sectional view of the third embodiment of the invention rain gutter. 
     FIG. 3B a plan view of part of the surface of an alternate configuration of the third embodiment of the invention rain gutter. 
     FIG. 4 is a perspective view of a fourth embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 4A is a cross sectional view of the fourth embodiment of the invention rain gutter. 
     FIG. 4B is a plan view of part of the surface of the fourth embodiment of the invention rain gutter. 
     FIG. 5 is a perspective view of a fifth embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 5A is a cross sectional view of the fifth embodiment of the invention rain gutter. 
     FIG. 6 is a front view of a sixth embodiment of the invention rain gutter shown mounted to a building. 
     FIG. 6A is a cross sectional side view of the sixth embodiment of the invention rain gutter. 
     FIG. 7 is a perspective view of a rain gutter cover that is a seventh embodiment of present invention. 
     FIG. 7A is a sectional view of the rain gutter cover of the seventh embodiment takent from plane A—A of FIG.  7 . 
     FIG. 7B is a sectional view of the rain gutter cover of the seventh embodiment takent from plane B—B of FIG.  7 . 
    
    
     DETAILED DESCRIPTION 
     Description of the First Embodiment 
     Turning now to the drawings, wherein like reference numerals designate identical or corresponding parts, and more particularly to FIG. 1 thereof, an invention rain gutter  10  is shown mounted to building  12 . As can be seen in FIG. 1, building  12  includes a roof  14 , shingles  16  and a wall  18 . Rain gutter  10  has a channel  22 , a collecting flange  30  and a support flange  60  that is supported by clips  70 . Channel  22 , as shown in FIG. 1, is formed in a circular or polygonal cross section for carrying rain water  24 . Collecting flange  30  is generally flat and can be inserted under the bottom row of shingles  16  and fixed to roof  14 . Support flange  60  can be bent back from channel  22  at an acute angle to receive clips  70  as shown in FIG.  1 . 
     Collecting flange  30  extends tangent from channel  22  and covers channel  22 . Collecting surface  30  of rain gutter  10  has a pattern of diagonal openings  32 . Between diagonal openings  32  are gaps  34  that are located above collecting slots  36 . It is important that collecting slots  36  be substantially wider than gaps  34 . Collecting slots  36  include inwardly bent tabs  38  that depend from the upper edges of the collecting slots. Channel  22 , in FIG. 1, is shown to have a plurality of longitudinal creases  42  which define the intersections of the polygonal sides of channel  22 . Alternatively, channel  22  can be formed from a rolled section having no creases such as creases  42 . Although in this preferred embodiment, a generally circular cross section has been selected for channel  22 , any cross section shape can be selected for conveying water. A series of clips  70  can be secured to wall  18  along a graded line so that gutter  10  can be mounted at a slight angle to allow water to flow along channel  22 . 
     FIG. 1B provides a close up plan view of the surface of collecting flange  30 . FIG. 1B also shows pairs of overlapping openings  32 , gaps  34 A and  34 B and collecting slots  36 A and  36 B having inwardly folding tabs  38 A and  38 B. Each pair of overlapping openings  32 , includes a first diagonal opening  32 A and second diagonal opening  32 B. First diagonal opening  32 A is defined by two parallel edges  32 A 1  and  32 A 2 . Second diagonal opening  32 B is similarly defined by two parallel edges  32 B 1  and  32 B 2 . Stream lines  46  visualize the flow of water down the surface of collecting flange  30 . A sheet of water flowing along stream lines  46  will develop surface tension as it contacts the surface of collecting flange  30 . That is, as water flows along stream lines  46  over the surface of collecting flange  30 , it will tend to adhere to the surface of collecting flange  30 . Consequently, as moving film of water encounters edge  32 A 1 , it will be diverted and run along edge  32 A 1  toward gap  34 A forming a small, fast moving stream of water. However, the flow of water will only be diverted if the angle of attack of the water as it encounters edge  32 A 1  not significantly greater than 45° and if edge  32 A 1  is clean and sharp. In the same way, as water flows to edge  32 B 1 , it will be diverted and run along edge  32 B 1  toward gap  34 B, when the angle of attack is not significantly greater than 45° and if edge  32 B 1  is clean and sharp. Accordingly, slots  32 A and  32 B do not collect water but rather divert water as they function as barriers as water forms small, fast moving streams along edges  32 A 1  and  32 B 1 . After the relatively small, fast moving water streams through gaps  34 A and  34 B, they encounter collecting slots  36 A and  36 B. Each stream of water continues to adhere to the surface of collecting flange  30  and therefore flows onto the inwardly folding tabs  38 A and  38 B and then drains into the interior of channel  22 . 
     Collecting flange  30  should be fashioned from a clean piece of painted sheet metal such as thin gauge aluminum having a non-glossy PVC coating. Thin gauge aluminum having a non-glossy PVC coating is generally hydrophilic. A surface that is highly water repellent would be very unsuitable. When flowing on a hydrophilic surface, water tends to adhere to that surface. This is known as the “Coanda Effect”. Because of the Coanda Effect, slots  32 A and  32 B shown in FIG. 1B function as barriers. Water will tend to flow along edges  32 A 1  and  32 B 1  even if it has to accelerate to flow through gaps  34 A and  34 B shown in FIG.  1 B. The recurring problem evident in the prior art, where arrangements are proposed for managing thin sheets of flowing water to convey water into a channel while excluding debris, has been the problem of inducing water on a collecting flange type surface to flow normal over an edge into a channel. The present invention solves this problem by using the property of water that causes it to resist flowing as a thin sheet normal to an edge to organize and concentrate the flow of water so that it can flow more easily across an edge and into a channel. Collecting surfaces, and even collecting slots of rain gutters of the present invention feature edges that are at least slightly angled in relation to the direction of flow of the water so that the Coanda Effect can be exploited to facilitate the collection of water while discouraging or even preventing the collection of debris. 
     The diagonal openings  32 A and  32 B shown here can be replaced with openings or cut outs having a wide variety of shapes. It is important that these openings have diagonal edges that confront the flow of water at reasonable angles of not more than 70°. Preferably, the diagonal edges should confront the flow of water at angles of not substantially more than 45°. If the force of surface adhesion that holds the water to the surface of collecting flange  30  is overcome by the acceleration force of the water diverting in a changed direction along an edge of a opening, then the water will jump over that edge. Water will be efficiently diverted only at smaller angles. However, if the small angle rule is followed, a large variety of openings can be employed. In fact, decorative shapes could be used to define the shapes of the openings. In this way an effective, closed rain gutter could be provided that is also decorative. Moreover, the volume under collecting flange  30  could be illuminated to create a decorative effect at night. The diagonal openings  32 A and  32 B could also be replaced by non-hydrophilic zones or inserts having a surface material that has little or no affinity for water such as Teflon®. Such water repelling inserts would cause the flow of water to pile up and divert in much the same way as would the openings described above. Such areas or inserts would have to be wide enough to prevent water from bridging over and flowing over an area or insert. Because water repelling zones would not effect the structural integrity of the collecting flange, such zones could be relatively large and could cover a substantial area of the surface of collecting flange  30 . 
     If the flow of water as represented by stream lines  46  is increased along the surface of collecting flange  30  as shown in FIG. 1B, then the partially diverted stream of water will begin to jump edge  32 A 1  and bridge across diagonal openings  32 A forming a concave trough that is suspended between edges  32 A 1  and  32 A 2 . The concave trough conveys a stream of water that runs parallel to edges  32 A 1  and  32 A 2  toward tab  38 A. A similar jumping and bridging process will occur in diagonal opening  32 B as the flow of water is increased. As the flow of water is further increased to a very high flow rate, it will overwhelm the capacity of the diagonal openings  32 A and  32 B and run over the side of gutter  10 . However, this very high flow rate is so large that it would overwhelm the capacity of channel  22  as well as the capacity of the downspout fed by channel  22 . 
     The applicant has observed that an article of debris such as a dead leaf or a twig that is carried by the flow of water over the surface of collecting flange  30  does not enter channel  22 . The applicant has also observed that even a small piece of debris does not have the ability to adhere to a surface as a stream of water adheres to a surface and therefore even a small piece of debris is separated from the flow of water and therefore does not divert into collecting slots  36 A or  36 B. Instead, such a foreign object will be ejected over the side of rain gutter  10 . A very small foreign object may be diverted into collecting slots  36 A or  36 B, but such an object would not large enough to obstruct a downspout and therefore would be washed out of the system. 
     When a circular cross section is selected for channel  22 , clips  70  can be secured at varying distances from wall  18  so that channel  22  can be formed into a gradual conical shape having a relatively small cross section at one end and a relatively large cross section at the other end where water is transferred to a downspout. This configuration would allow water to flow at a relatively constant velocity through channel  22  as the volume of flow increased closer to a downspout (not shown). Clips  70  can also be adjusted so that the bottom surface of rain gutter  10  can have a slight slope to further enhance the flow of water. Because rain gutter  10  is generally circular, because its cross section is adjustable as described above and because it can be mounted so that its bottom edge has a slight downward slope towards a downspout, the rain gutter will conduct flow at within in a narrower velocity range for wide range of volumetric flow rates than a prior art, constant cross section, flat bottomed rain gutter. This is because rain gutter  10  provides a gradually increasing cross sectional area as it fills with water. If rain gutter  10  is adjusted into a conical shape, the beginning of the rain gutter can have a smaller cross section where the volumetric flow rate is smaller. In this way, with the circular cross section combined with cross section adjustability, the velocity of the flow can be held relatively constant along the length of the gutter at a given drainage load, and even be held relatively constant along the length of the gutter over a range of drainage loads. 
     Second Embodiment 
     FIG.  2  and FIG. 2A illustrate a second rain gutter  200  which is a second embodiment of the present invention. Much as with the embodiments described above, rain gutter  200  can be fitted under shingles  16 . Rain gutter  200  includes a rain gutter channel  222  a support flange  260 , a mounting flange  220  and a collecting flange  230 . Just as with collecting flange  20  of rain gutter  10 , collecting surface  230  of rain gutter  200  has a pattern openings  232 . Openings  232  include a diagonal edge  233  and an inwardly bent collecting tab  235 . Inwardly bend collecting tab  235  intersects the surface of collecting flange  230  at a folded edge  234 . Collecting tab  235  has a lower edge  237  and a collecting tab corner  238 . Diagonal edge  233  and folded edge  234  meet at an upper corner  236 . 
     It might appear from casual observation that water flowing upon the surface collecting flange  230  would flow around upper corner  236  an along diagonal edge  233  to escape between the gaps between openings. This, however, is not the case. The flow of water that flows onto bent collecting tab  235 B of adjacent opening  232 B induces flow so that water flowing near corner  236  is drawn down on to collecting tab  235 B. This happens in part because collecting tab lower edge  237  slopes down toward collecting tab corner  238  so that water flowing on the surface of collecting tab  235  will, because of the Coanda Effect, tend to flow toward collecting tab corner  238 . Water will tend to flow along an edge even if that edge is not normal to the path of the water by only a small degree. The tendency of the water flowing on the surface of collecting tab  235  to flow along edge  237  sets up a transverse flow of water that induces water flowing around corner  238  to flow down on to collecting tab  235 B. By using this a single row of collecting slots having collecting tabs with angle lower edges, it is indeed possible to collect all or almost all of the water flowing over collecting flange  230  with a single row of slots. This can even occur if the collecting slots do not overlap. In this embodiment, as with other embodiments described herein, water tends to follow the path of least resistance and it tends to adhere to itself as it flows. This embodiment, as other embodiments described herein, shares the common strategy of using an angled edge, in this case an angled collecting tab lower edge  237 , to organize and direct the flow of water on a collecting surface. 
     As is the case with the embodiments described above, rain gutter  200  can be installed at a graded angle. Second rain gutter  200 , like rain gutter  10 , can be mounted to a roof and wall so that it can be adjusted along its length so that the cross sectional area of the channel at one end is larger than at the other end. The mounting flange  260  can also be adjusted so that the bottom surface of rain gutter  200  can have a slight slope to further enhance the flow of water. Because rain gutter  200  is generally circular at the channel portion, because its cross section is adjustable as described above and because it can be mounted so that its bottom surface has a slight downward slope, it too can be adjusted to conduct a flow of water at a relatively constant flow velocity along its length under varying drainage loads as described above with respect to rain gutter  10 . 
     Third Embodiment 
     FIG.  3  and FIG. 3A illustrate a third rain gutter  300  which is a third embodiment of the present invention. Much as with the embodiments described above, rain gutter  300  can be fitted under shingles  16 . Rain gutter  300  includes a rain gutter channel  322  a support flange  360 , a mounting flange  320  and a collecting surface  330 . With rain gutter  300 , the collecting flange  20  of rain gutter  10 , is replaced by an upper mounting flange  320  and a lower collecting surface  330 . Mounting flange  320  and collecting surface  330  of rain gutter  300  are separated by a small radius folded edge  324 . Collecting surface  330  includes an upper portion that curves toward the building and a lower portion that curves away from the building. Horizontal line  342  shown in FIG. 3A passes through the point where a line tangent to collection surface  330  would also be parallel to plumb line  340 . The radius of folded edge  324  should be substantially less than 0.5 inches and preferably about 0.10 inches. Just as with collecting flange  20  of rain gutter  10 , collecting surface  330  or rain gutter  300  has a pattern of diagonal openings  332 . Between diagonal openings  332  are gaps  334  that are located above collecting slots  336 . It is important that collecting slots  336  be located on that portion of the collecting surface that is sloping away from the building and toward the outer wall of channel  322 . It is also important that collecting slots  336  be substantially wider than gaps  334 . As is more clearly shown in FIG. 3A, collecting tabs  338  fold in from the top edges of collecting slots  336 , inwardly and away from collecting surface  330 . As can be seen in FIG. 3A, collecting surface  330  can slope inwardly in relation to a plumb line  340  which is defined as a vertical line tangent to folded edge  324 . Mounting flange  320  may also include, at its lower edge, a pooling zone  321 . Pooling zone,  321  is a slightly indented area. The build up of water in pooling zone  321  tends to force debris past folded edge  324 . 
     As with rain gutter  10 , diagonal openings  332  of rain gutter  300  direct the flow of water into gaps  334  where it flows into collecting slots  336  and down into channel  322 . It is important that diagonal openings  332  have diagonal edges that confront the flow of water at reasonable angles of not substantially more than 45°. The tendency of water to adhere to a surface is known as the Coanda Effect. As the diagonal edges of diagonal openings  332  converge, the water flowing between those edges flows faster over a smaller area of collecting surface  330 . As the stream of water flows down onto collecting tabs  338 , because it is by then a small, fast moving stream, it can easily separate from collecting tabs  338  and drain down in to channel  322 . If the force of surface adhesion that holds the water to the surface of collecting surface  330  is overcome by the acceleration force of the water diverting in a changed direction along an edge of a opening, then the water will jump over that edge. Water will be efficiently diverted only at smaller angles. However, if the small angle rule is followed, a large variety of openings can be employed. 
     FIG. 3B illustrates that the diagonal openings  332  could be replaced by water repelling zones  332 B that have little or no affinity for water. Such water repelling zones could be fashioned by coating the indicated surface with a material such as Teflon®. Such a water repelling zone would cause the flow of water to divert in much the same way as would openings  332  in FIG.  3 . Preferably, as shown in FIG. 3B, water repelling zones should be wide enough to prevent water from bridging over a zone to escape. Water repelling zones  332 B could be superior to diagonal openings because they would not be able to catch debris. The use of water repelling zones  332 B shown in FIG. 3B to redirect the flow of water on collecting surface  330 B illustrates a key aspect of the present invention. Diagonal opening  332  in the hydrophilic collecting surface  330  of FIG. 3 functions in the same way as a zone that has a water repelling surface. Because of this, a diagonal opening such as diagonal opening  332  of FIG. 3 may be considered as a “non-hydrophilic zone”, just as a zone having a water repellent coating may also be considered as a “non-hydrophilic zone”. What is key to the present invention is that the boundary between the hydrophilic surface of the collecting surface and a non-hydrophilic zone can be oriented with respect to the direction of the flow of water at a non-normal angle so that the flow of water will change direction when it encounters the boundary. Collecting slots  336 B shown in FIG. 3B have a curved shape so that the bottom edges of inwardly bent tabs  338 B also have a curved shape. The curved bottom edges of inwardly bent tabs  338 B cause water to move down the curved edges toward the center of each tab to further induce the flow of water into collecting slots  336 B. Collecting slots  336 B illustrate that a collecting slot may have other than a horizontal or rectangular shape and thereby function more effectively to collect water. 
     It may appear from casual observation that a film of water will not flow around folded edge  324 . This might be true if the film of water flowing down collecting surface  330  were eventually confronted by a series of normal edges, and this would be especially true if those normal edges were confronted near or above line  342 . However, if water is accelerated and effectively pulled across collecting surface  330  as it is when it encounters diagonal openings  332 , then water flows easily around folded edge  324 . Accordingly, with collecting surface  330 , a thin film of water can be drawn around folded edge  324  while debris that can not negotiate folded edge  324  is easily ejected. The inventor has found that a thin film of water will flow more easily around folded edge  324  if collecting surface  330  especially in the area of folded edge  324  has surface texture features that are generally normal to folded edge  324 . A hydrophilic PVC coated surface could for example have a surface grain that is generally perpendicular to folded edge  324 . When the surface of collecting surface  330  has this type of texture with this type of orientation, the flow of water around edge  324  is established more rapidly than when there is no surface texture. 
     As is the case with rain gutter  10 , rain gutter  300  can be installed at a graded angle. Third rain gutter  300 , like rain gutter  10 , can be mounted to a roof and wall so that it can be adjusted along its length so that the cross sectional area of the channel at one end is larger than at the other end. The mounting flange  360  can also be adjusted so that the bottom surface of rain gutter  300  can have a slight slope to further enhance the flow of water. Because rain gutter  300  is generally circular at the channel portion, because its cross section is adjustable as described above and because it can be mounted so that its bottom surface has a slight downward slope, it too can be adjusted to conduct a flow of water at a relatively constant flow velocity along its length under varying drainage loads as described above with respect to rain gutter  10 . It may appear from casual observation that a sheet of water would not flow around. 
     Rain gutter  300  is able to eject almost all debris from the system because rain a film of water can easily navigate folded angular edge  324  but the debris absolutely cannot make the sharp turn at folded angular edge  324  and is completely ejected from the system. Rain Gutter  10  will reject most debris, but rain gutter  300  will simply not allow any debris except very small debris to enter channel  322 . 
     Fourth Embodiment 
     FIG. 4, FIG.  4 A and FIG. 4B illustrate rain gutter  400 , which is a fourth embodiment of the present invention. Much as with the embodiments described above, rain gutter  400  can be fitted under shingles  16  and includes a mounting flange  420 , a collecting surface  430 , a channel  422 , and a support flange  460 . As can be seen in FIG.  4  and FIG. 4A, collecting surface  430  curves inwardly in relation to a plumb line  440  under a folded, angular edge  424 . Accordingly, collecting surface  430  is located under mounting flange  420  and above channel  422 . Arranged on collecting surface  430  are diagonal openings  432 . A pooling area  421  runs just above and parallel to folded edge  424 . 
     Diagonal openings  432  are shown in greater detail in FIG.  4 B. Diagonal openings  432  include a long leg  434  and a short leg  436  that intersect at an angle. Diagonal openings  432  are arranged so that each long leg  434  substantially overlaps the adjacent short leg  436 . The vertical position of diagonal openings  432  is illustrated in FIG. 4A. A flow of water  480  shown in FIG. 4B travels along the top edge of long leg  434  and even up a portion of the top edge of short leg  436  for a short distance against the force of gravity. However, flow of water  480  is overcome by gravity and loses adhesion with the upper edge of opening  432  where the top edges of long leg  434  and short leg  436  meet and drains into channel  422  of rain gutter  400 . This loss of adhesion and flow into channel  422  occurs because flow of water  480  can only flow down into channel  422 . Because diagonal openings  432  are positioned on the surface of collecting surface  430  so that the lower edge of opening  422  is below horizontal line  442  and closer to plum line  440 , flow of water  480  can easily pass down into channel  422 . As flow of water  480  is increased, the more energetic component of flow from long portion  432  causes the flow to assume a direction more parallel with long portion  434 . Diagonal openings  432  can be adjusted in size and width so that their cumulative capacity is substantially the same as the capacity of cannel  422 . 
     As is the case with the embodiments described above, rain gutter  400  can also be installed at a graded angle and installed to vary the cross sectional area of its channel along its length so that it too can be adjusted to conduct a flow of water at a relatively constant flow velocity along its length under varying drainage loads. 
     Rain gutter  400  is able to eject almost all debris from the system because a film of water can easily navigate folded angular edge  424  but the debris cannot make the sharp turn at folded angular edge  424  and is completely ejected from the system. Because with rain gutter  400 , diagonal openings  432  are covered by mounting flange  420 , even falling debris can not enter channel  422 . Rain gutter  400  is easier to produce than the rain gutters described above because collecting surface  430  has fewer openings and no inwardly bent collecting tabs. 
     Fifth Embodiment 
     FIG. 5, and FIG. 5A illustrate rain gutter  500 , which is a fifth embodiment of the present invention. Much as with the embodiments described above, rain gutter  500  can be fitted under shingles  16  and includes a mounting flange  520 , a collecting surface  530 , a channel  522 , and a support flange  560 . As can be seen in FIG.  5  and FIG. 5A, the collecting surface  530  curves inwardly under a folded, angular edge  524  in relation to a plumb line  540 . Collecting surface  530  is located under mounting flange  520  and above channel  522 . Pooling area  521  runs just above and parallel to folded edge  524 . Arranged on the surface of collecting surface  530  are overlapping collecting slots  532 . 
     Collecting slots  532 , as shown in FIG.  5  and FIG. 5A, are arranged on collecting surface  530  in at least two staggered rows so that water flowing on collecting surface  530  is captured by one of the slots. Starting at the top edge of each collecting slot  532  is an inwardly bent tab  534  that acts to direct water down into channel  522 . Collecting slots  532  can be adjusted in size and width so that their cumulative capacity is substantially the same as the capacity of cannel  522 . 
     As is the case with the embodiments described above, rain gutter  500  can also be installed at a graded angle and installed to vary the cross sectional area of its channel along its length so that it too can be adjusted to conduct a flow of water at a relatively constant flow velocity along its length under varying drainage loads. 
     Rain gutter  500  is able to eject almost all debris from the system because rain a film of water can easily navigate folded angular edge  524  but the debris absolutely cannot make the sharp turn at folded angular edge  524  and is completely ejected from the system. Because collecting slots  532  are covered by mounting flange  520 , even falling debris can not invade channel  522 . 
     Sixth Embodiment 
     FIG. 6, and FIG. 6A illustrate rain gutter cover  600 , which is a sixth embodiment of the present invention. Rain gutter cover  600  is not a complete gutter system but rather is a cover that can be placed over a conventional gutter  15 . Rain gutter cover  600  illustrates that the present invention can be applied to a cover that will convert a conventional rain gutter into one having the elements of the present invention. As shown in FIG. 6A, gutter cover  600  can be fitted under shingles  16  and includes a mounting flange  620  and a collecting surface  630 . As can be seen in FIG.  6  and FIG. 6A, the collecting surface  630  curves inwardly under a folded, angular edge  624  in relation to a plumb line  640 . Collecting surface  630  is located under mounting flange  620  and above conventional gutter  15 . Arranged on the surface of collecting surface  630  are diagonal openings  632  and collecting slots  636 . 
     Diagonal openings  632  and collecting slots  636 , as shown in FIG.  6  and FIG. 6A, are arranged on collecting surface  630  so that water flowing on collecting surface  630  is diverted by diagonal openings  632  and then captured by collecting slots  636 . Starting at the top edge of each collecting slot  632  is an inwardly bent tab  638  that acts to direct water down into above conventional gutter  15 . Collecting slots  636  are located below horizontal line  642  which crosses through a point on collecting surface  630  where a line tangent to surface  630  would be parallel to plumb line  640 . That is, collecting slots  636  should be located on that portion of the collecting surface that is curving back toward plumb line  640  and away from the building. 
     Rain gutter cover  600  is able to eject almost all debris from the system because rain a film of water can easily navigate folded angular edge  624  but the debris absolutely cannot make the sharp turn at folded angular edge  624  and is completely ejected from the system. Because collecting slots  632  are covered by mounting flange  620 , even falling debris can not invade conventional gutter  15 . 
     It should be noted that it is possible to place any combination of the diverting and collecting openings present in rain gutters  10  and  200  shown in FIG.  1  and FIG. 2 respectively on an inwardly curved collecting surface such as surface  430  of rain gutter  400  shown in FIG. 4 or surface  530  of rain gutter  500  shown in FIG.  5 . It should also be noted that any one of the configurations shown can be adapted to define a cover that can be added to a conventional gutter as is the case with gutter cover  600  shown in FIG.  6  and FIG.  6 A. 
     Seventh Embodiment 
     FIG. 7 illustrates rain gutter cover  700 , which is a seventh embodiment of the present invention. Rain gutter cover  700  is not a complete gutter system but rather it is a cover that can be placed over a conventional gutter such as gutter  15  shown in FIG.  6 . Even though rain gutter cover  700  is not a complete gutter, the concepts of the design of gutter cover  700  can easily be applied to a complete, enclosed gutter. Rain gutter cover  700  embodies an approach to diverting water across a surface towards a water collecting opening that is somewhat different than the approach used in the embodiments described above. Rain gutter cover  700  is fashioned so that it has a very contoured surface. The surfaces of Rain gutter cover  700  are not flat along contours of constant elevation as they tend to be with the embodiments described above. The channeling of rain water with rain gutter cover  700  is accomplished by using edges that are angled in relation to normal direction of the flow of water, but those angled edges do not result from cut outs in thin sheets of material. With rain gutter cover  700 , the angled or sloped edges are present at the edges of features that project out in relation to the adjacent surface of the rain gutter. In rain gutter cover  700 , these features include curved, channeling features  732  and  734  that originate at the lower edge of mounting flange  720  and channeling feature  736  that curves between collecting openings in collecting flange  730 . Water follows the edges of the curved channeling features  732 ,  734  and  736  in much the same way and for some of the same physical reasons that water will follow the edge of a cut out in a sheet of material. However, these curved, channeling features  732 ,  734  and  736  do not present a means for collecting debris. Although wet debris may adhere to channeling features  732 ,  734  and  736 , when it does so, water can still flow under the wet debris. When the debris dries it will fall away from gutter cover  700 . Channeling features  732 ,  734  and  736  can be used to direct the flow of rain water to surprisingly small openings that are virtually impervious to the entry of debris. 
     Rain gutter cover  700  includes a mounting flange  720 , a rounded edge  724 , a collecting flange  730  and a mounting step  750 . Mounting step  750  includes two upright walls  750 A and  750 B and a generally horizontal wall  750 C. Mounting step  750  makes it possible to easily install rain gutter cover  700  where existing gutters have varying widths or locations in relation to the roof line of the building. Originating just above rounded edge  724  on mounting flange  720  and sloping down across collecting flange  730  are two channeling features  732  and  734 . Channeling feature  736  curves along the surface of collecting flange  730  between collecting openings  738 . These channeling features and collecting opening  738  are symmetrical about plane B—B in FIG.  7 . Their function is to divide up a flowing film of water that flows down mounting flange  720  and organize it into separate streams that flow across collecting flange  730  and down into collecting opening  738 . Although in this example three channeling features are shown, it may be possible to direct substantially all of the water flowing as a film on mounting flange  720  into opening  738  with one or a combination of two of the three channeling features shown. 
     As can be seen in more detail in FIG.  7 A and FIG. 7B, first channeling feature  732 , second channeling feature  734  and third channeling feature  736  are raised, curved features having curved cross sections. As shown in FIG. 7B, channeling feature  732  includes two opposite edges  732 A and a channeling surface  732 B that extends to those edges. Channeling surface  732 B can be generally flat along a contour of constant elevation or could, in some areas, have turned up edges as shown in FIG.  7 A. Channeling feature  734  includes a turned up edge  734 A and channeling surface  734 B that curves inwardly to provide a reduction in profile so that edge  732 A of channeling feature  732  can be formed. Similarly, channeling feature  736  includes an edge  736 A and channeling surface  736 B which also curves inwardly to causing a reduction of the thickness of collecting flange  730  so that edge  734 A of channeling feature  734  can be formed. 
     Channeling features  732  and  734  wrap around rounded edge  724  and taper out at the lower end of mounting flange  720 . Because the function of channeling features  732  and  734  is to organize a flowing film of water into streams of water that flow toward and eventually into collecting opening  738 , it is important to not extend channeling features  732  and  734  a significant distance up on to mounting flange  720 . If channeling features  732  and  734  are extended a significant distance up on to mounting flange  720 , then fast moving streams of water will be organized that can not flow around rounded edge  724  without separating from rounded edge  724 . The centripetal force of such a stream of water will overcome its adhesion to the surface which will cause it to separate at rounded edge  724 . However, if rounded edge  724  is given a relatively large radius, it is then possible to extend channeling features  732  and  734  up on to mounting flange  720  by a greater distance because the centripetal force acting on the stream decreases as the radius of rounded edge  724  increases. 
     As can be seen in FIG. 7A, channeling features  732 ,  734  and  736  converge above collecting opening  738 . A drain feature  740  is located on the underside of gutter cover  720  just below collecting opening  738 . Drain feature  740  is shaped to release a flow of water down into a gutter channel. Drain feature  740  is useful for a gutter cover as shown in FIG. 7 because if water adheres to the underside of gutter cover  700 , it will flow down to and possibly over the edge of the gutter that it is covering. Drain feature  740  would be less useful in a complete gutter as opposed to a gutter cover but would still be useful for organizing and pulling the stream of water down into the gutter channel. 
     Although gutter cover  700  has been illustrated with an inwardly turned collecting flange  730 , channeling features such as channeling features  732 ,  734  and  736  and collecting openings such as collecting opening  738  could be incorporated into an enclosed rain gutter such as rain gutter  10  shown in FIG.  1 . The resulting rain gutter using the water channeling concepts of rain gutter cover  700  would be made from some moldable material such as plastic. Such a rain gutter would have many of the same advantages as a gutter or gutter cover having an inwardly turned collecting surface. 
     Gutter cover  700  provides significant advantages. It is almost impossible for debris to follow the torturous path from mounting flange  720  into collecting opening  738 . Pine needles are a significant problem in many areas of the United States. Although pine needles tend to orient in direction that is normal to the direction of a moving film of water and tend to cling to edges and then collect in the slots and openings of prior art enclosed gutters, pine needles can not adhere to the edges of this contoured gutter cover. Pine needles will separate at rounded edge  724  because it has an uneven, almost stepped surface and be rejected by cover  700 . Rain gutter cover  700  is almost perfectly adapted to collect only rain water and reject virtually any type of debris. Moreover, rain gutter cover  700  is capable of collecting a flow of rain water that would be large enough to overwhelm a downspout. As noted above, a gutter system has too much collecting capacity if that collecting capacity is greater than the downspout capacity. 
     The skilled reader will find a common thread in most of the embodiments described above. Water will tend to flow around a curved surface and adhere to an overhanging surface because of the surface tension property of water. Because of the Coanda effect, water will tend to flow along an edge that is oriented against a grade. By using the property of surface tension to move water upon overhanging surfaces and the Coanda effect to direct water along edges that are angled in relation to the grade of a surface, it is possible to devise water collecting gutters that will draw in rain water but that will reject debris that would obstruct a rain gutter. 
     In view of the numerous embodiments described above, numerous modifications and variations of the preferred embodiments disclosed herein are possible and will occur to those skilled in the art in view of this description. For example, many functions and advantages are described for the preferred embodiments, but in some uses of the invention, not all of these functions and advantages would be needed. Therefore, I contemplate the use of the invention using fewer than the complete set of noted functions and advantages. Moreover, several species and embodiments of the invention are disclosed herein, but not all are specifically claimed, although all are covered by generic claims. Nevertheless, it is my intention that each and every one of these species and embodiments, and the equivalents thereof, be encompassed and protected within the scope of the following claims, and no dedication to the public is intended by virtue of the lack of claims specific to any individual species. Accordingly, it is expressly to be understood that these modifications and variations, and the equivalents thereof, are to be considered within the spirit and scope of the invention as defined by the following claims, wherein, I claim: