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FIELD OF THE INVENTION  
         [0001]    A barrier installed in a curbside drain opening which detains solid trash from entering the drain when there is no or slow water flow, but which opens fully when a sufficiently high water flow rate occurs.  
         BACKGROUND OF THE INVENTION  
         [0002]    A barrier installed in a curbside drain opening which detains solid trash at no or slow rate flow rates, but which opens when the rate is sufficiently high, is shown in Martinez U.S. Pat. No. 6,217,756. The objective of this patent, and of the instant invention, is to impede the entrance of solid trash into the drain from a gutter while permitting slow water flow, and to open up when the flow is heavy so as to pass it.  
           [0003]    Of course, when a heavy flow of water arrives and the barrier opens, whatever solid trash is already detained at the opening, or is up the gutter, will be washed into the drain. However, when there is no flow, or only slow flow, the detained trash can readily be swept away by a street sweeper. In effect, this barrier keeps out of the downstream drain system trash which accumulates during dry periods if the street is properly swept.  
           [0004]    Municipalities are well aware of the costs when trash enters a drainage system. Generally there is a catch basin into which water and trash that passed through the drain opening are deposited. This trash must be removed, usually on a periodic basis. A heavy cover is removed, and then depending on what is in there, a man must go into the basin properly equipped to clear it out. If for some reason the basin is not properly cleaned out, and a rapid flow of water arrives, the drain can be plugged, and a flood ensues. Proper maintenance is necessary.  
           [0005]    Of even greater concern is what arrives downstream from the basin. Sooner or later, all material that is not removed near the source will reach a water system. In some states this is a river or lake. In others it is an ocean or a bay. In every such situation, there result troublesome accumulations of trash and often pollution. These events often occur at places where it is difficult to retrieve the trash, and sometimes it is too late, especially when soluble or small particles are involved and they are dispersed into the environment.  
           [0006]    To counter the risk, and depending on the scope of the drainage system, catch dams are often provided downstream which must periodically be cleaned out at great expense. It is best practice to exclude trash from them to the maximum extent possible while they are dry, and while the trash is readily accumulated in condition for easier collection at the curbside.  
           [0007]    Still, means for this purpose should not interfere with the primary objective of the drainage system, which is to protect the surrounding area against flooding when the flow is heavy, such as in hard rainstorms or thunderstorms. In those events, the system must be maximally open and cannot be permitted to plug up. Apparatus according to this invention helps to assure system open-ness, because it can prevent most of the trash from entering the system in the first place.  
           [0008]    An inherent problem with known devices such as in the aforementioned Martinez patent is that, while they need to remain open during times of heavy flow, they should close when the flow slows, but still stay open in case the system has already opened and then backs up and floods the catch basin. The said patented device can lose its control function when the system backs up, and the barrier can close, which can result in a flooded condition.  
           [0009]    It is an object of this invention to provide a barrier that is normally closed during no or slow water flow rates, is reliably open when the rates increase, and reliably closes when the water in the basin recedes.  
           [0010]    Optionally, means can be provided to keep the barrier open whenever the water level in the basin rises above some reference level and there may be no adequate flow past the control to keep the barrier open. With this improvement the system&#39;s control devices cannot be overwhelmed by being immersed in standing water in a flooded basin.  
         BRIEF DESCRIPTION OF THE INVENTION  
         [0011]    Apparatus according to this invention is intended to be installed in a curbside drain opening. Such openings receive water from a gutter, which often entrains solid trash such as leaves, cuttings, bottles, and papers. The opening is usually vertical and rectangular. At its lower edge is a lip across which water and whatever else is carried by it, will flow and pass.  
           [0012]    The apparatus is installed as a controllable barrier between the gutter and a catch basin. Such a catch basin is generally accessible from above, open to flow from the opening and connected to a downstream drainage system. Such systems customarily drain to a place where rainfall ultimately arrives—a water treatment facility, a river, a bay, or an ocean.  
           [0013]    These systems can be clogged up by trash at any point. It is best practice to keep the trash out as much as possible. According to this invention, the barrier of this invention stays closed when there is no or only slow water flow. This will exclude trash from the system, while permitting the flow of water at lesser flow rates. Trash detained in the gutter can be swept away at any time without entering the catch basin or anyplace else in the system.  
           [0014]    According to this invention, the barrier is pivotally mounted to structure surrounding the curbside drain, adapted to remain across the drain opening when there is no or only slow flow of water from the gutter. Linkage is mounted to the structure and to the barrier to rotate the barrier between closed and opened positions.  
           [0015]    An actuator responsive to the flow rate of water through the opening is positioned inside of the basin below the lower edge of the opening, where water flow at a higher flow rate will flow into a receptacle, but water at a slower rate will not. The actuator includes a receptacle which, when sufficiently filled, will cause the actuator to move the linkage and open the barrier.  
           [0016]    According to this invention, as soon as the barrier is opened, the receptacle will tilt and dump its load of water. This eliminates the weight which opened the barrier. Without further provisions, the barrier would simply be closed again, even if the water flow continued. It is a feature of this invention that, after the receptacle has dumped its contents, it remains effective on the actuator so long as a sufficient water flow impacts on it.  
           [0017]    Then, as an additional but optional feature, should the receptacle be immersed in a flooded basin, means can be provided to hold the barrier open until the water in the basin recedes below the flooded level.  
           [0018]    The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which: 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    [0019]FIG. 1 is a fragmentary perspective view of a region incorporating the invention;  
         [0020]    [0020]FIG. 2 is a perspective inside view showing the presently-preferred embodiment of the invention installed in a catch basin;  
         [0021]    [0021]FIG. 3 is a right hand side view of the apparatus of FIG. 2 in its closed condition;  
         [0022]    [0022]FIG. 4 is a right hand side view of FIG. 3, showing the system starting to open;  
         [0023]    [0023]FIG. 5 is a right hand view showing the system fully open in a continuing rapid flow of water;  
         [0024]    [0024]FIG. 6 is a right hand side view showing a flooded-out condition;  
         [0025]    [0025]FIG. 7 is a perspective view of a frame useful in this apparatus;  
         [0026]    [0026]FIG. 8 is an exploded view showing the relationship of several parts of the apparatus;  
         [0027]    [0027]FIG. 9 is a perspective view as in FIG. 2, showing a modified part of the apparatus, the system being closed; and  
         [0028]    [0028]FIG. 10 is a side view of a portion of FIG. 9, showing the system fully open.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0029]    A typical installation for this invention is shown in FIG. 1. A curb  10  next to a gutter  11  has a drain opening  12  which is usually rectangular. The opening has a bottom edge  13  over which water will follow when it enters the opening.  
         [0030]    In turn the opening enters into a catch basin  14  (FIG. 3). Essentially this is a small “room” with a top in which a manhole  15  or other entry arrangement is fitted with a removable cover  16 . From the catch basin, a conduit  17  leads into a drainage system, usually a storm drain intended to carry away water at flow rates which, if not carried away would flood surrounding areas. As stated before, these basins must be kept free of amounts of trash that could clog them, or depending on the nature of the trash, contaminate or cause flooding downstream.  
         [0031]    Although the individual parts of the apparatus could be directly attached to structure of the curb and of the basin, it is best manufacturing procedure to provide a structure which can be fitted in or attached to the surrounding opening.  
         [0032]    A frame  18  (FIGS. 2, 3 and  7 ) includes two springy mounting arms  22 ,  23  formed to a V-shape. Brackets  24 ,  25  are attached to the arms so this structure can be attached to the wall of the drain opening. As shown in FIG. 7, these arms are springy, so as to cause them when installed to bear strongly against the wall of the drain opening. The dashed lines in FIG. 7 show the distorted, installed free ends, while in solid line are shown the undistorted ends prior to installation.  
         [0033]    A brace  30  is attached to the two mounting arms to hold the base together. Attachment pins  31 ,  32 ,  33  and  34  provide for attachments which will later be described.  
         [0034]    Barrier  41  is a flat structure with dimensions of length and of height. It is pivoted to pins  32  and  34  at the bottom edge  13  of the opening. When erect the barrier will occlude the opening, at least in part. It may conveniently be a grating or a grid of rods or wires, or a screen, depending on what is anticipated to be the type of trash to be detained and the anticipated rates of flow. In any event, some kind of space or clearance next to, beside or below the barrier, will be provided to enable the slow flow of water past the barrier when it is closed, and over edge  13 .  
         [0035]    The slow flow (FIG. 3) is designated by arrows  42 . This slow flow simply drips over the bottom edge, and into the basin, without having any effect on this device. Except, of course that trash which it brings to the opening will be detained by the closed barrier.  
         [0036]    Importantly, at this time the barrier is locked closed. Attention is called to the over-center alignment of arms to be described as best shown in FIG. 3. As will later be shown, mechanical forces against it will not open it. Most importantly, brooms or sweepers can sweep past it to carry away the trash without opening the barrier. Thus, the system&#39;s trash load is greatly reduced. The only trash which will ultimately enter the catch basin is what is present in the gutter when heavy water flow occurs. The trash load for what is most of the rest of the year will be excluded from the catch basin, and thereby from the rest of the system.  
         [0037]    There remains to be disclosed the controls to maintain the drainage system mechanically closed to entry of trash while permitting slow flow of water, to open it while the flow is rapid, and to keep the closure open when the drainage system itself is flooded.  
         [0038]    A tiltable receptacle  50  is pivotally supported from a pair of suspensions  51 ,  52  that are hinged to the end walls  53 ,  54  of the receptacle. The receptacle is an open topped container, preferably V-shaped, with a pair of side faces  55 ,  56  and the two end walls. A bias flange  57  extends beyond side face  55  for a purpose to be described.  
         [0039]    A trip chain  58  extends between an attachment point  59  near the bottom apex of the receptacle, and pin  60  on an arm of the frame. There preferably will be one of these chains at each end of the receptacle.  
         [0040]    Actuator links  65 ,  66  are mounted to arms  22 ,  23  at each side. Together they mount and support a counterweight  67 . These links include identical levers  68 ,  69  with rigidly joined arms  70 ,  71 . These arms rotate with the counterweight. Pivot points  74 ,  75  mount these links to the arms at their joinder.  
         [0041]    A pivot bar  80  extends between the joinders  81 ,  82  of the links  65  and  66  and mounting links  83 ,  84 . Mounting links  83  and  84  are hinged to the suspensions  51 ,  52  and to brackets  85 ,  86  (FIG. 8) on the closure. A limit flange  87  extends from arm  71  to contact arm  84  to limit the upward movement of suspension  52 .  
         [0042]    The operation of this device as described to this point is as follows. Starting with the closed condition of FIG. 3, the barrier is erect, and solid trash (not shown) will be detained in the gutter. Slow flow  42  of water drips over edge  13 , and does not enter the receptacle. This is the normal condition. The slow flow often will come from over-watering of lawns, the washing of cars, and light rains.  
         [0043]    Heavier flows  43 , as shown in FIG. 4 will not only drip over the edge, but will project into the system, where some of it will fall into the receptacle. There it will accumulate and start to overcome the counterweight. Notice that until this time, as in FIG. 3, force against the barrier was resisted by the aligned link elements, preferably with a slight over-center alignment.  
         [0044]    The accumulated weight of water pulls down on the linkage, raises the counterweight and starts to open the barrier. Notice that the water continues to pour into the receptacle. The receptacle does not have a drain.  
         [0045]    Next, as the receptacle fills sufficiently, the chain and the suspension are lowered. Soon the chain will trip the receptacle to the tilted position of FIG. 5. One would expect the loss of weight in the receptacle to enable the counterweight to close the barrier. It would, except that with sufficiently high rates of flow, water will cascade down onto bias flange  57 . Its force on the flange will hold the receptacle in the tilted position, and the barrier open, so long as the high rate of flow persists (FIG. 5). When it stops, the counterweight will again return the system to its closed position, because the receptacle is empty, or sufficiently empty as to enable the closure to occur.  
         [0046]    [0046]FIGS. 9 and 10 show that, instead of a bias flange on the receptacle facing the curbside, a lip  90  can be placed on the backside of the receptacle, preferably forming an open ended trough  91 . This trough will also be impacted by high rates of flow, and will tend to keep the barrier from closing, as before.  
         [0047]    [0047]FIG. 6 illustrates a latch-open feature of the invention which will be effective to keep the barrier open when the downstream system in the catch basin is flooded. A float  100  is supported by arm  101 . A second arm  102  rigidly attached to arm  101  forms a lever. The arms are pivotally mounted to the frame at hinge  103 . A catch surface  104  on arm  102  can overlap the edge of the open barrier when the water level  105  in the catch basin rises to the extent shown, before it can flood out the receptacle. If the water rises above that, the float and catch surface keep the closure open so the flooding of the basin will not affect the closure.  
         [0048]    This invention is not to be limited by the embodiments shown in the drawings and described in the description, which are given by way of example and not of limitation, but only in accordance with the scope of the appended claims.

Summary:
A system to exclude trash from curbside drains during periods of no or slow water flow, but opening to permit full entry during heavier flow such as during heavy rains. The system may have a linkage preventing opening by force on its barrier, and to assure that it will remain open should downstream drainage systems become flooded.