Abstract:
A modular rainwater storage tank configured to allow storage capacity in a small area when positioned around the corner of a rectangular house or other structure utilizing run off from a roof top. The storage tank may be designed as a three-dimensional quarter-round such that three units will fit in a tight configuration around a right angle. Each storage tank has opposing overflow channels in a raised rim enclosing a recess in the lid. Downspout water is directed to an opening in the raised rim. When the storage tank is full, excess water in the recess in the lid may be directed to an adjacent storage tank in a cascaded configuration. In this manner, three storage tanks may be positioned and cascaded around a corner.

Description:
TECHNICAL FIELD 
     This invention relates in general to a modular storage tank and system for catching and storing rainwater. 
     BACKGROUND AND SUMMARY 
     Typical rainwater storage tanks have some method of directing rainwater from the roof of a structure into an opening in the storage tank. Some method is also included that allows stored rainwater to be extracted from the storage tank. Prior art storage tanks are designed to be singular (typically cylindrical) storage tanks with little consideration for geometry or modularity. 
     A modular rainwater storage tank is designed as a three-dimensional quarter-round shape in embodiments of the present invention. One or more of the modular units may be positioned next to a house or other structure from which rainwater runoff is to be captured. The storage tank is designed with a fill opening and an over flow that allows water from the primary storage tank, connected to a downspout, to be directed to an optional second, third, fourth, etc. storage tank. The quarter-round design allows three storage tanks to be efficiently positioned around a right angled corner while increasing the rigidity of the storage tank system. The quarter-round shape increases the rigidity over a typical square storage tank. While a square storage tank has increased volume, the radius R of the quarter-round storage tank need only be increased to 1.128R to have a volume equal to a square storage tank with side equal to R. The top of the storage tank may have a raised rim wide enough to place a fill hole the size of a downspout. The raised rim has one or more channels configured so adjacent storage tanks may be coupled with a channel piece that aids in directing overflow water between storage tanks. An overflow adapter or a water block may be positioned in an overflow channel depending on whether multiple storage tanks are cascade-connected via a channel piece positioned in adjacent channels. A U-shaped clip may be inserted over the raised rims of adjacent storage tanks to increase the rigidity of a multiple storage tank system. A side wall of a storage tank may have a threaded hole configured to accept a faucet for draining each storage tank. 
     In alternative embodiments, the top lid of the tank is sloped so that the rainwater flows towards a fill hole. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1A  illustrates an embodiment showing a quarter-round geometry of a storage tank with channel features for cascading water flow from one storage tank to another; 
         FIG. 1B  illustrates a curved side of the storage tank of  FIG. 1  including a faucet suitable for extracting stored water; 
         FIG. 2  illustrates the storage tank of  FIG. 1  coupled to a downspout pipe with a water block for stopping water flow, a channel piece for conducting water from one storage tank to another, and a clip for securing one storage tank to another in a cascaded configuration; 
         FIG. 3A  is a top view of three exemplary storage tanks positioned at the corner of a structure and further illustrating the use of exemplary clips, channel pieces, and water blocks; 
         FIG. 3B  is a top view of two exemplary storage tanks positioned along the wall of a structure also illustrating the use of a clip, a channel piece, and water blocks; 
         FIG. 3C  is a top view of a single exemplary storage tank positioned in an inside corner of a structure; 
         FIG. 4  illustrates a single exemplary storage tank with a water block in one channel and a flexible overflow hose connected to a channel piece in a second channel; and 
         FIGS. 5A-9B  illustrate alternative embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1A  illustrates a perspective view of a hollow rainwater storage tank  101  according to embodiments herein. A cross-section of the storage tank  101  has a quarter-round shape with a top lid  112  having a raised rim  121  forming a recess  102 . Note that the storage tank is not to be limited to a right-angled quarter-round shape, but may be configured to have any cross-section shape. The raised rim  121  has one or more channel features  103 ,  104 , and  110 . These channel features are suitably configured to accept an exemplary hollow channel piece  105 . The channel piece  105  allows overflow water collected in recess  102  to be channeled to a second storage tank (see  FIGS. 3A-3B ). Any channel feature  103 ,  104 ,  110  not used to transport overflow water may be fitted with a water block  106  to prevent water loss. The channel feature  110  may be formed on the curved side of the rim  121  and may be additionally fitted with a channel piece  105  so that overflow water of a single storage tank may be directed away from any structure positioned next to the storage tank  101 . An exemplary clip  109  may be configured to fit over the raised rims  121  on two adjacent units  101  to provide structural support when adjoining two or more storage tanks  101 . A clip  109  may have its sides angled towards each other requiring the sides to be sprung outward to insert over the raised rims  121  of adjacent storage tanks  101  thus providing additional holding force. 
     The storage tank  101  is hollow and receives water (e.g., rainwater) into a fill opening  108  from a structure&#39;s rainwater downspout  201  (see  FIG. 2 ). As water completely fills the tank  101 , it will overflow into the recess  102  from the overflow opening  107  in the lid  112 . The overflow opening  107  is configured to allow overflow water to begin to fill the recess  102 . As water fills the recess  102 , the water is directed to any channel (e.g.,  103 ,  104 , or  110 ) not blocked by a water block  106 . The fill opening  108  is configured to accept a downspout (see  FIG. 2 ) and may be positioned in the rim area  121  so that inlet water can continue to flow into the storage tank  101  while over flow water from the opening  107  flows into the recess  102 . The fill opening  108  may be positioned anywhere on the tank  101 ; the opening  107  may be utilized as a fill opening. While the channels  103 ,  104 ,  110  are shown as generally rectangular in shape, it is understood that other geometries may be used for these channels and corresponding fitted elements, the channel piece  105 , and the water block  106 . 
     Alternatively, a downspout  201  may be positioned over a lid of the storage tanks described herein so that the rainwater is directed to flow onto the recess  102 ,  502  (see  FIGS. 5A-5B ), or  602  (see  FIGS. 6A-9B ). 
     The storage tank  101  may be configured as a two-piece unit having a separable lid  112  (e.g., to simplify manufacture). In such an embodiment, the lid  112  would have a parting line  113  when installed and may be configured so that the parting line  113  corresponds substantially to the level of the opening  107 . Therefore, water in any storage tank  101  will only rise slightly above the opening  107  before flowing to a next storage tank; thus, little water may leak at the parting line  113  where the lid  112  attaches to the lower body of the storage tank  101 . 
       FIG. 1B  is a view of a storage tank  101  showing the curved side  130 . The curved side  130  is not limited to the shape shown. Positioned on the curved side  130  may be an exemplary drain faucet  111 , which may be attached to a hose (not shown) suitable for extracting water from the storage tank  101 . The channels  103 ,  104 , and  110 , as well as the fill hole  108 , the overflow hole  107 , and the recess  102  are shown in this view. A faucet  111  may be positioned sufficiently close to the bottom so that most all of the water in the storage tank  101  may be drained. It is also understood that water may also be extracted from the storage tank  101  by using a siphon or pump (not shown) positioned via an unused fill or overflow hole (e.g.,  108  or  107 ). All of the embodiments described herein may be configured for such ways of extracting the water from the tank(s). 
       FIG. 2  is a view of a storage tank  101  showing a channel piece  105  inserted in one channel (e.g.,  104 ) and a water block  106  inserted in another channel (e.g.,  103 ); a channel  110  is shown open, though it may be fitted with a water block  106 . In this view, the lid  112  has a fill hole  108  in the rim  121  of the storage tank  101  with a section of a downspout  201  inserted. A recess  102  is shown with an overflow hole  107 . In an embodiment, the overflow hole  107  is substantially at the same level as a parting line  113  to reduce leakage. In this embodiment, the top  112  may be configured with a U-shaped lip that extends over the top edges of the sides of the body  131  of the storage tank  101 . An insert  150  shows a cross-section of the U-shaped lip and the fit between the lid  112  and the body  131  of the storage tank  101  suitable to reduce leakage and improves storage tank rigidity when the lid  112  is in place. 
       FIG. 3A  illustrates a top view of three storage tanks  101 A,  101 B, and  101 C (where each of the tanks  101 A,  101 B, and  101 C are substantially configured similar to the tank  101  in  FIGS. 1A-2 ), configured as a storage system  300  so that it can be positioned around a corner of a structure  301  to receive rainwater from the structure via a downspout (see  FIG. 2 ). The three storage tanks,  101 A,  101 B,  101 C, may be held together with clips  109 A and  109 B fitted over corresponding raised rims  121 A,  121 B,  121 C. The adjacent channels  103 A,  103 B and  104 B,  104 C of the storage tanks  101 A,  101 B and  101 B,  101 C, respectively, may be each fitted with a channel piece  105 A and  105 B, respectively. In this manner, only one of the fill holes ( 108 A.  108 B,  108 C) in the storage tanks  101 A,  101 B,  101 C, respectively, need be coupled to a downspout (e.g.,  201  in  FIG. 2 ) supplying rainwater from the structure  301 . The other two storage tanks without the downspout are filled by cascaded overflow through the channel pieces  105 A,  105 B. For example, if a downspout (e.g.,  201  in  FIG. 2 ) is coupled to the fill hole  108 B, then rainwater will initially fill up the storage take  101 B. When such rainwater rises within the storage tank  101 B to the opening  107 B, it will begin filling the recess  102 B and then will flow through one or both of the channels  105 A,  105 B into the recesses  102 A,  102 C, respectively, to then begin filling one or both of the storage tanks  101 A,  101 C through the openings  107 A,  107 C, respectively. 
     Water blocks  106 A,  106 B,  106 C may be installed in any unused channels  104 A,  110 A,  110 B,  110 C,  103 C to prevent leakage through the unused channels. Faucets  111 A,  111 B,  111 C may be used to extract water from the storage tanks  101 A,  101 B,  101 C, respectively. When all three storage tanks are full, water may be extracted via one of the faucets  111 A,  111 B,  111 C, or one of the water blocks  106 A,  106 B,  106 C may be removed to allow overflow water to drain to the ground. 
       FIG. 3B  illustrates a top view of two storage tanks  101 A,  101 B (where each of the storage tanks  101 A,  101 B are substantially configured as the tank  101  in  FIGS. 1A-2 ), configured as a storage system  310  so that it can be positioned along a structure  302 . The storage tanks  101 A,  101 B each have an overflow hole  107 A,  107 B, respectively. Fill holes  108 A,  108 B are located in the raised rims  121 A,  121 B of the storage tank  101 A,  101 B, respectively. One or more clips  109 A may be used to hold the storage tanks  101 A,  101 B together. Water blocks  106 A,  106 B may be positioned in any unused channels  104 A,  104 B. Faucets  111 A,  111 B may be located in the curved walls  130 A,  130 B of the storage tanks  101 A,  101 B, respectively, and may be used to extract water. A channel piece  105 A may be positioned in adjoining channels  103 A,  103 B on, adjacent walls of the storage tanks  101 A,  101 B. Similarly as with the storage system  300 , the storage system  310  may operate to permit the filling of one or both of the tanks  101 A,  101 B regardless of which tank is coupled to a downspout. 
       FIG. 3C  illustrates a top view of a water storage system  320  comprising a single storage tank  101  positioned along an inside corner of a structure  303 . In this embodiment, the channels  103 ,  104 ,  110  have a water block  106  inserted to stop water leakage when the storage tank  101  is full. A downspout (e.g.,  201  in  FIG. 2 ) is coupled to the fill hole  108 . A faucet  111  may be used to extract stored water. 
       FIG. 4  illustrates a perspective view of an embodiment of a storage tank  101  having a flexible hose  401  coupled to a channel piece  105  used to direct overflow water away from the storage tank  101 . All of the embodiments described herein may be configured with a similar configuration. A channel  110  is shown open, and the other channel, has a water block  106  inserted. An overflow hole  107  is positioned in the recess  102 . Alternative embodiments to the foregoing may be configured so that water is merely directed into one or more of the recesses  102  instead of via one or more fill holes  108 . In this manner, the water will drain from the one or more recesses  102  into the tank body via an overflow hole  107 . All of the embodiments described herein may be configured with a similar configuration. 
       FIGS. 5A-5B  illustrate embodiments whereby any number of adjacent storage tanks are bolted together in place of the use of the clips  109  shown in  FIGS. 3A-3B . The storage tank  501  illustrated in  FIG. 5A  is similar to the storage tank  101  illustrated in  FIG. 1A . However, a lid  512  is configured with one or more holes  514 - 517  therethrough for receiving bolts  503 - 506  (or any equivalent fastening means) as shown in  FIG. 5B  for fastening together two or more storage units  101 . 
       FIGS. 6A-9B  illustrate embodiments where instead of channeling water between units through channels  105 , the tops of the units are sloped.  FIGS. 6A-6C  illustrate such a single storage container  601 , which is similar to the storage container  101  (not all features are repeated in  FIGS. 6A-7B  for the sake of simplicity). A downspout (not shown) may drain water into the storage container  601  through a hole (e.g., hole  607 ) or on its top  602  where it flows into the hole  607 . Two tanks  601  are combined in  FIGS. 7A-7B  where water can overflow from the top of one tank  601  to the other(s) over the depression  702  in the respective lids of the tanks. 
     One or more splashguards  608 ,  609  may be installed (e.g., via some suitable fastening means, such as screws or bolts) along the sloping edges of the top  602  of the tank  601  to channel the water flowing on the top  602  towards the hole  607 , so that such water does not flow over the edges of the top  602 .  FIGS. 7A-7B  show a similar splashguard  701  (or multiple splashguards in a suitable combination) installed along edges of the tops  602  of the tanks  601  to channel water from both of the tops  602  towards the holes  607 , including overflow from one of the tanks  601  to the other, without allowing water to escape over the edges of the tops  602  outside of the tanks  601 . Though not illustrated, a similar system of splashguard(s) may be installed on a three-tank configuration (see  FIG. 3A ). 
       FIGS. 8A-8C  and  9 A- 9 B illustrate similar configurations of tanks as shown in  FIGS. 6A-6C  and  7 A- 7 B, respectively, with a variation in the slopes of the tops  802 .  FIGS. 8A-8C  illustrate such a single storage container  801 , which is similar to the storage container  101  (not all features are repeated in  FIGS. 8A-9B  for the sake of simplicity). A downspout (not shown) may drain water into the storage container  801  through a hole (e.g., hole  807 ) or on its top  802  where it flows into the hole  807 . Two tanks  801  are combined in  FIGS. 9A-9B  where water can overflow from the top of one tank  801  to the other. 
     One or more splashguards  808 ,  809  may be installed (e.g., via some suitable fastening means, such as screws or bolts) along the sloping edges of the top  802  of the tank  801  to channel the water flowing on the top  802  towards the hole  807 , so that such water does not flow over the edges of the top  802 .  FIGS. 9A-9B  show a similar splashguard  902  (or multiple splashguards in a suitable combination) installed along edges of the tops  802  of the tanks  801  to channel water from both of the tops  802  towards the holes  807 , including overflow from one of the tanks  801  to the other, without allowing water to escape over the edges of the tops  802  outside of the tanks  801 . Though not illustrated, a similar system of splashguard(s) may be installed on a three-tank configuration (see  FIG. 3A ). 
     Alternative embodiments may have shapes other than the quarter-round shapes. The number of channels in a rim may be one or greater. Other means for extracting the water from a tank may be utilized other than a faucet.