Flow Control System

Abstract

An application for a flow control system includes a vertically oriented expanding conduit, positioned within the interior of a container which is fluidly interfaced to a downstream drainage system. The lower end of the expanding conduit is in fluid communication with an upstream reservoir through a closed conduit. A means to restrain the expanding conduit from lateral movement is provided and the means is in fluid communication with the interior of the container. The distal, upper end of the expanding conduit is capped and at least one fluid passageway opens through the cap from the interior of the expanding conduit. As the fluid pressure rises in the expanding conduit in response to an increase in the fluid level in the upstream reservoir, the fluid passageway through the capped, upper end of the expanding conduit rises to prescribed level and the release rate of fluid into the downstream drainage system is maintained at a prescribed rate or range of rates as the fluid level continues to rise.

Claims

1. A flow control system for integration into detention ponds, surge tanks, reservoirs and other applications wherein upstream fluid levels vary in response to varying rates of inflow, the flow control system comprising: a container, the container having an interior, the container interior being maintained at an ambient, atmospheric pressure being fluidly connected to a downstream drainage system; a closed conduit, the closed conduit having an upstream end opening into a reservoir, the closed conduit having a downstream end within the container interior opening upward; an expanding conduit, an axis of which is vertical, the expanding conduit having an interior, the lower end fluidly connected to said closed conduit downstream end, the expanding conduit distal, upper end having a cap with an underside comprising a surface which fluid pressure within the expanding conduit can exert and upward force against and at least one fluid passageway which opens from the expanding conduit interior; a means to restrain the expanding conduit from lateral movement, said means having an interior fluidly connected to said container interior; whereas fluid flows from the upstream reservoir through the closed conduit, upward through the expanding conduit, exerts an upwards force against the surface which fluid within the expanding conduit can exert an upward pressure against, flows out through at least one fluid passageway opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, into the interior of the means to restrain the expanding conduit from lateral movement, into the container interior and out into the downstream drainage system; whereby expansion of the expanding conduit is achieved through pressure increase in the interior of the expanding conduit created by the fluid flowing through the expanding conduit.

2. The flow control system of claim 1, wherein the at least one fluid passageway, opening from the expanding conduit interior, said expanding conduit interior having an inner dimension and inner area, through the expanding conduit distal, capped, upper end, is oriented horizontally and has an open area smaller than the inner area of the inner dimension of the expanding conduit thereby creating a surface which fluid within the expanding conduit can exert an upward pressure against.

3. The flow control system of claim 1, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented vertically.

4. The flow control system of claim 1, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is provided in the form of a tube; the tube exiting into and being fluidly connected to the container interior.

5. The flow control system of claim 1, wherein the expanding conduit is a bellows.

6. The flow control system of claim 1, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube; an axis of which is vertical, the rigid tube having an interior, the rigid tube interior enclosing the expanding conduit, the rigid tube having at least one opening, along the axis of the rigid tube which is vertical, fluidly connecting the rigid tube interior to the container interior.

7. The flow control system of claim 6, wherein the at least one opening fluidly connecting the rigid tube interior to the container interior is a slot along the axis of the rigid tube.

8. The flow control system of claim 1, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, oriented vertically, the array of rigid bars having an interior and enclosing the expanding conduit within the interior of the array, the array of rigid bars having space between the rigid bars such that the interior of the array of rigid bars is fluidly connected to the container interior.

9. The flow control system of claim 5, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented horizontally and has an open area smaller than the area of the inner dimension of the expanding conduit thereby creating a surface which fluid within the expanding conduit can exert an upward pressure against.

10. The flow control system of claim 5, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented vertically.

11. The flow control system of claim 5, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is provided in the form of a tube; the tube exiting into and being fluidly connected to the container interior.

12. The flow control system of claim 5, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube; an axis of which is vertical, having an interior enclosing the expanding conduit, having at least one opening along the length of the axis of the rigid tube which is vertical fluidly connecting the rigid tube interior to the container interior.

13. The flow control system of claim 12, wherein the at least one opening fluidly connecting the rigid tube interior to the container interior is a slot along the axis of the rigid tube.

14. The flow control system of claim 5, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, enclosing the expanding conduit within the interior of the array, having space between the rigid bars such that the interior is fluidly connected to the container interior.

15. The flow control system of claim 11, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube, an axis of which is vertical, having a length, an exterior dimension, an interior dimension, and at least one slot, said interior dimension enclosing the expanding conduit, said at least one slot having a length and a width, along the length of its the axis of the rigid tube which is vertical, the width of the at least one slot being sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

16. The flow control system of claim 11, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, enclosing the expanding conduit within the interior of the array, having space between the rigid bars sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

17. A flow control system for integration into a holding tank, the flow control system comprising: a container, installed within a holding tank, the container having an upper end which is open, the container having an upper rim positioned at a prescribed level, the container having an interior being maintained at an ambient, atmospheric pressure within the holding tank, and being fluidly connected to a downstream drainage system; a closed conduit, the closed conduit having an upstream end opening into the holding tank, having a downstream end within the container interior, and having a downstream end opening upward; an expanding conduit, an axis of which is vertical, having an interior with an inner dimension and inner area, a lower end fluidly connected to said closed conduit downstream end, the expanding conduit distal, upper end having a cap, through which at least one fluid passageway opens from the expanding conduit interior; a means to restrain the expanding conduit from lateral movement, said means having an interior fluidly connected to the container interior; whereas fluid flows from the holding tank through the closed conduit, upward through the expanding conduit, out through the at least one fluid passageway opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, into the interior of the means to restrain the expanding conduit from lateral movement, into the container interior and out into the downstream drainage system; whereas, when the fluid level in the holding tank rises above the prescribed level of the upper rim of the container, the fluid also flows over the upper rim of the container; into the interior of the container and out into the downstream drainage system.

18. The flow control system of claim 17, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented horizontally and has an open area smaller than the inner area of the inner dimension of the expanding conduit.

19. The flow control system of claim 17, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented vertically.

20. The flow control system of claim 17, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is provided in the form of a tube; said tube having an interior and exterior dimension, the tube exiting into and being fluidly connected to the container interior.

21. The flow control system of claim 17, wherein the expanding conduit is a bellows.

22. The flow control system of claim 17, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube; an axis of which is vertical, the rigid tube having an interior, the rigid tube interior enclosing the expanding conduit, the rigid tube having at least one opening, along the the axis of the rigid tube which is vertical, fluidly connecting the rigid tube interior to the container interior.

23. The flow control system of claim 22, wherein the at least one opening fluidly connecting the rigid tube interior to the container interior is a slot along the axis of the rigid tube.

24. The flow control system of claim 17, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, enclosing the expanding conduit within the interior of the array, having space between the rigid bars such that the interior of the array of rigid bars is fluidly connected to the container interior.

25. The flow control system of claim 20, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube, an axis of which is vertical, the rigid tube having an interior, the rigid tube interior enclosing the expanding conduit, the rigid tube having at least one slot, said at least one slot having a length and width along the axis of the rigid tube which is vertical, the width of the at least one slot being sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

26. The flow control system of claim 20, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, the array of rigid bars enclosing the expanding conduit within the interior of the array, the array of rigid bars having space between the rigid bars sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

27. A flow control system for integration into a reservoir, the flow control system comprising: a container, the container being in communication with the fluid in the reservoir, having an overflow weir through a wall of the container and positioned at a prescribed level, the container having an interior being maintained at an ambient, atmospheric pressure, the container interior being fluidly connected to a downstream drainage system; a closed conduit having an upstream end opening into a reservoir, and having a downstream end within the container interior, said downstream end opening upward; an expanding conduit, an axis of which is vertical, the expanding conduit having an interior with an inner dimension and inner area, said expanding conduit also having a lower end, the lower end fluidly connected to said closed conduit downstream end, the expanding conduit distal, upper end having a cap, through which at least one fluid passageway opens from the expanding conduit interior; a means to restrain the expanding conduit from lateral movement, having an interior fluidly connected to the container interior; whereas fluid flows from the reservoir through the closed conduit, upward through the expanding conduit, out through the at least one fluid passageway opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, into the interior of the means to restrain the expanding conduit from lateral movement, into the container interior and out into the downstream drainage system; whereas, when the fluid level in the reservoir rises above the prescribed level of the overflow weir, the fluid also flows over the overflow weir, into the interior of the container and out into the downstream drainage system.

28. The flow control system of claim 27, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented horizontally and has an open area smaller than the inner area of the inner dimension of the expanding conduit.

29. The flow control system of claim 27, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is oriented vertically

30. The flow control system of claim 27, wherein the at least one fluid passageway, opening from the expanding conduit interior through the expanding conduit distal, capped, upper end, is provided in the form of a tube having an interior and exterior dimension; the tube exiting into and being fluidly connected to the container interior.

31. The flow control system of claim 27, wherein the expanding conduit is a bellows.

32. The flow control system of claim 27, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube; an axis of which is vertical, the rigid tube having an interior, the rigid tube interior enclosing the expanding conduit, the rigid tube having at least one opening along the the axis of the rigid tube which is vertical fluidly connecting the rigid tube interior to the container interior.

33. The flow control system of claim 32, wherein the at least one opening fluidly connecting the rigid tube interior to the container interior is a slot along the axis of the rigid tube.

34. The flow control system of claim 27, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, the array of rigid bars enclosing the expanding conduit within the interior of the array, the array of rigid bars having space between the rigid bars such that the interior of the array of rigid bars is fluidly connected to the container interior.

35. The flow control system of claim 30, wherein the means to restrain the expanding conduit from lateral movement is a rigid tube, an axis of which is vertical, the rigid tube having an interior enclosing the expanding conduit, the rigid tube having at least one slot, said at least one slot having a length and width, along the length of its the axis of the rigid tube which is vertical, the width of the at least one slot being sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

36. The flow control system of claim 30, wherein the means to restrain the expanding conduit from lateral movement is an array of rigid bars, having an interior and oriented vertically, the array of rigid bars enclosing the expanding conduit within the interior of the array, the array of rigid bars having space between the rigid bars sufficient to accommodate the exterior dimension of the tube exiting into the container interior.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which:

[0017] FIG. 1 illustrates a schematic of a system of the present invention wherein the fluid level in the upstream reservoir is at its initial, minimum, controlled level;

[0018] FIG. 2 illustrates a schematic of a system of the present invention wherein the fluid level in the upstream reservoir has risen above its minimum, controlled level;

[0019] FIG. 3 illustrates a perspective view of the distal, capped, upper end of the expanding conduit of a first embodiment of the present invention;

[0020] FIG. 3A illustrates a perspective view of an alternate distal, capped, upper end of the expanding conduit of a first embodiment of the present invention;

[0021] FIG. 3B illustrates a perspective view of the distal, capped, upper end of the expanding conduit of a second embodiment of the present invention;

[0022] FIG. 3C illustrates a perspective view of the distal, capped, upper end of the expanding conduit of a third embodiment of the present invention;

[0023] FIG. 4 illustrates a perspective view of the expanding conduit enclosed within a means to prevent lateral movement of a first embodiment of the present invention;

[0024] FIG. 4A illustrates a perspective view of the expanding conduit enclosed within an alternate means to prevent lateral movement of the present invention;

[0025] FIG. 4B illustrates a perspective view of the expanding conduit of a first embodiment of the present invention enclosed by a second alternate means to prevent lateral movement;

[0026] FIG. 4C illustrates a perspective view of the expanding conduit enclosed within a third alternate means to prevent lateral movement of the present invention;

[0027] FIG. 5 illustrates a schematic of an alternate embodiment of the present invention;

[0028] FIG. 6 illustrates a schematic of a second alternate embodiment of the present invention;

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENT

[0029] Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. Throughout the following description, the terms fluid handling system, detention pond, surge tank, holding tank, reservoir, and other applications wherein upstream fluid levels vary, represent any such structure and are equivalent structure for storing a fluid and discharging it at a prescribed, desirable rate or range of rates as the case may be.

[0030] The flow control system described provides for an initial discharge rate starting as soon as the upstream reservoir reaches a pre-determined, minimum, controlled fluid level. Then, as the fluid level increases, the discharge rate is controlled at a prescribed rate or range of rates until a high-water level is reached, at which level the flow control system provides for an increased discharge rate to reduce the possibility of exceeding the volumetric capacity of upstream reservoir.

[0031] Prior to more advanced flow control systems, limiting the maximum outflow rates was accomplished by the use of fixed weirs and orifices, flow control systems whereby the discharge was controlled in response to the movement of a float, or the bias of a spring, or flow control systems wherein a flexible conduit is immersed in such a manner that the pressure outside of the flexible conduit is greater than the pressure inside of the flexible conduit. Fixed weirs and orifices can only control the discharge rate within a broad range, determined by the range of the fluid level fluctuation in the upstream reservoir. Flow control systems whereby the discharge rate is controlled in response to the movement of floats can be subject to failure if hollow floats are ruptured. Solid displacement float can also suffer a decrease in their net buoyancy, over time, if the floats are formed from materials which have the propensity to absorb fluid. Flow control systems whereby the discharge rate is controlled in response to the bias from a spring can fail, over time, due to decreasing bias caused by strain and repeated cyclical motion, and metallic springs are vulnerable to the effects of corrosion from a variety of elemental exposures. Flow control systems wherein a flexible conduit is immersed in fluid, such that the pressure outside of the flexible conduit is greater than the pressure inside of the flexible conduit, are known to have a very limited range of depth at which they may operate without subjecting the flexible conduit to pressures at which the flexible conduit will collapse. The present invention solves these and other problems as is evident in the following description.

[0032] Referring to FIG. 1, a schematic view of a system of the present invention will be described. The flow control system 30 is incorporated into a fluid handling system 10 wherein the flow control system 30 receives the flow of fluid 3 from an upstream reservoir 1 and discharges the flow to a downstream drainage system 60.

[0033] The flow control system 30 consists of four primary components; a closed conduit 31, an expanding conduit in the form of a bellows 40 which is restrained from lateral movement, a cap 45, and a container 20. The closed conduit 31 is made of plastic, metal, concrete or any other material which is suitable for conveying the fluid 3, and is connected to the upstream reservoir 1 below the fluid surface 2. The downstream end of the closed conduit 31 is oriented such that its exit is directed upward and it is interfaced to the lower end of the bellows 40. The upstream end of the closed conduit 31 is equipped with an optional baffle 32, to prevent entry of undesirable materials such as trash, debris, greases, oils and the like from entering or possibly interfering with the operation of the flow control system 30. Although the optional baffle 32 is depicted in the form of an elbow oriented such that its entrance is directed downward, there are many ways to protect the inlet of the closed conduit 31 from the unwanted entry of undesirable materials. In some embodiments it is anticipated the closed conduit 31 may be protected by a screen, or by connecting its inlet to a surface skimming device.

[0034] The bellows 40 has an axis which is vertical and is made from rubber, polyurethane, plastic or any other any reasonably flexible, resilient and impervious material suitable for conveying the fluid 3. Although there are many ways to interface the lower end of the bellows 40 to the closed conduit 31, the lower end of the bellows 40 is connected to the closed conduit 31 by means of a flanged connection 35. In some embodiments it is anticipated the lower end of the bellows 40 has a collar which fits tightly over the outside of the closed conduit 31 and is fastened to the closed conduit 31 with clamps.

[0035] The distal, upper end of the bellows 40 is equipped with a cap 45 which is made from metal, plastic or any other sufficiently rigid material suitable for exposure to the fluid 3. The cap 45 has at least one fluid passageway 46 which provides an opening from the interior of the bellows 40. The fluid passageway 46 is oriented horizontally and has an open area which is smaller than the cross sectional area of the inner dimension of the bellows 40. In some embodiments, the cap 45 is a component which is separate, and is fastened to the upper end of the bellows 40. In other embodiments, the cap 45 is made integral to the bellows 40.

[0036] The bellows 40 is enclosed by a rigid tube 50, an axis of which is vertical, and which has a slot 51 provided along the length of its axis of sufficient width such that the interior of the rigid tube 50 is freely and fluidly connected to the interior of the container 20. Although only a single slot 51 is shown, it is anticipated that in some embodiments there may be more than one slot 51. The interior dimension of the rigid tube 50 is sufficient to accommodate the exterior dimension of the bellows 40 such that the bellows 40 is free to expand upwardly, yet is restrained from moving laterally. The rigid tube 50 is made of metal, plastic or any other material which is suitable for exposure to the fluid 3 and is sufficiently rigid to maintain its axis vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces.

[0037] The container 20 can be fashioned from materials such as concrete, metal, plastic or any other material or combination of materials which provide adequate structural integrity and are also reasonably impervious and suitable for exposure to the fluid 3. In some embodiments, the upper end of the container 20 may be open, and in other embodiments it may be closed, so long as the interior container 20 can be maintained at the ambient, atmospheric pressure. An overflow riser 90 is located downstream of the container 20 and is fluidly interfaced to the downstream drainage system 60, at a point which is downstream from the container 20. The overflow riser 90 is made of concrete, metal, plastic or any other material which has adequate structural integrity and is suitable for conveying discharges of fluid 3. When the fluid surface 2 in the reservoir 1 has risen to a level above the upper rim 91 of the overflow riser 90, the overflow riser 90 provides a means to accommodate an increased rate of discharge when the volumetric capacity of the reservoir 1 is in danger of being exceeded. Although both the container 20 and the overflow riser 90 are depicted as being positioned in the reservoir 1, it is not required. In some embodiments it is anticipated that the container 20 may be located outside of the reservoir 1 and the overflow riser 90 may be connected to the downstream drainage system 60 at a point downstream from the container 20 by means of a pipe which is routed around the container 20. The position of the overflow riser 90 within the flow control system 30 may be at any of a number of locations so long as its upper rim 91 is fluidly connected to the reservoir 1 and it is connected to the downstream drainage system 60 at a point which is downstream from the container 20.

[0038] The bellows 40 is depicted in a less than fully expanded state and the fluid passageway 46 through the cap 45 is at an initial level, at which the fluid surface 2 in the reservoir 1 is at the same level, and is the minimum, controlled level, at which there is no flow and no discharge of fluid 3 from the flow control system 30 into the downstream drainage system 60.

[0039] Referring to FIG. 2, a schematic view of a system of the present invention will now be described. The flow control system 30 and fluid handling system 10 are the same flow control system 30 and fluid handling system 10 depicted in FIG. 1., wherein the flow control system 30 is incorporated into a fluid handling system 10, and wherein the flow control system 30 receives the flow of fluid 3 from an upstream reservoir 1 and discharges the flow to a downstream drainage system 60. The fluid surface 2 in the upstream reservoir 1 has risen above the initial, minimum, controlled level and the fluid 3 is flowing through the flow control system 30 from the upstream reservoir 1, through the optional baffle 32, into the closed conduit 31, upward through the bellows 40, and out through the fluid passageway 46, provided through the cap 45, and into the interior of the rigid tube 50, wherein it then freely discharges out through the slot 51 along the length of the vertical axis of the rigid tube 50 into the container 20 and out into the downstream drainage system 60. Since the fluid passageway 46 through the cap 45 has an open area which is smaller than the cross sectional area of the inner dimension of the bellows 40, the bellows 40 has expanded upward in response to the increase in system pressure caused by the rise of the fluid surface 2 in the upstream reservoir 1 and, in turn, the level of the fluid passageway 46 through the cap 45 has risen to a prescribed level which is below the fluid surface 2 in the upstream reservoir 1, and the rate of flow through the flow control system 30 is maintained at the desirable release rate or range of release rates prescribed for the fluid handling system 10.

[0040] Referring to FIG. 3, a perspective view of the distal, upper end of the bellows 40 of a first embodiment of the present invention will be described. The distal, upper end of the bellows 40 is fitted with a cap 45 through which a fluid passageway 46 is provided. The open area of the fluid passageway 46 is smaller than the area of the inner dimensions of the bellows 40. Although the bellows 40 is depicted as having a circular cross section, the bellows 40 may have a cross section of any geometry and it is anticipated that in some embodiments the bellows 40 may have a cross section which is non-circular. Similarly, the fluid passageway 46 is also depicted as being a single, circular opening; however, it may be provided in any number of a plurality of openings and geometric configurations suitable for limiting the release rate to the desirable release rate prescribed for the application. The cap 45 is in the form of a plate which is firmly attached to the bellows 40 in a fluid tight manner by an array of fasteners 47. The cap 45 can be made of metal, plastic, or any other material which provides sufficient strength and rigidity to convey the upward force of increasing pressure, through the array of fasteners 47 to the upper end of the bellows 40. The fasteners 47 may be screws, bolts, pins, staples or any other type of fastener suitable for making a firm and fluid tight connection to the distal, upper end of the bellows 40; however, the fasteners are optional as a firm and fluid tight connection between the cap 45 and the upper end of the bellows 40 may also be accomplished by a flanged connection, or by welding, fusing or the use of adhesives.

[0041] Referring to FIG. 3A, a perspective view of an alternate distal, upper end of the bellows 40 of a first embodiment of the present invention will be described. The distal, upper end of the bellows 40 is formed with an integral collar, into which a cap 45, through which there is a fluid passageway 46 which has an open area less than the cross sectional area of the inner dimension of the bellows 40, has been inserted and fastened to upper end of the bellows 40 in a firm and fluid tight manner with a hose clamp 48. Although a single hose clamp 48 is depicted, it may be one or a plurality of hose clamps of any type and material suitable for making a firm and fluid tight connection between the integral collar provided at the upper end of the bellows 40 and that portion of the cap 45 which has been inserted into the integral collar at the upper end of the bellows 40. Further, the hose clamp 48 is optional as a firm and fluid tight connection can also be accomplished by welding, fusing or the use of adhesives. Although the fluid passageway 46 is depicted as being a single, circular opening; it may be provided in any number of a plurality of openings and geometric configurations suitable for limiting the release rate to the desirable release rate prescribed for the application.

[0042] Referring to FIG. 3B, a perspective view of the upper end of the bellows 40 of a second embodiment of the present invention will be described. The distal, upper end of the bellows 40 is fitted with a cap 45 through which a plurality of fluid passageways 46 have been provided, in an orientation which is vertical, such that the discharge from the interior of the bellows 40 is directed horizontally. Although a plurality of fluid passageways 46 are depicted, only a single fluid passageway 46 is required so long as it is of sufficient area to limit the flow rate to the desirable release rate for the application. When the fluid passageway(s) 46 are oriented vertically, as shown, it is not necessary that they have an open area which is less than the cross sectional area of the inner dimensions of the bellows 40. The cap 45 is fastened to the upper end of the bellows 40 in a firm and fluid tight manner by any number of means which accomplish such a connection, and further, it is not necessary that the cap 45 be provided as a separate part, as it may be made integral to the bellows 40.

[0043] Referring to FIG. 3C, a perspective view of the distal, upper end of the bellows 40 of a third embodiment of the present invention will be described. The distal, upper end of the bellows 40 has been fitted with a cap 45, through which a plurality of fluid passageways 49, are provided in the form of a short tube oriented such that its exit into the interior of the container is directed downward. The fluid passageways 49 intersect the vertical axis of the cap 45 and open from the interior of the bellows 40. Although a plurality of fluid passageways 49 are depicted, only a single fluid passageway 49 is required, so long as it is of sufficient area to pass the desired release rate for the application. Whereas the fluid passageways 49 intersect the vertical axis of the cap 45, it is not necessary that they have an open area which is less than the cross sectional area of the inner dimensions of the bellows 40 and it is anticipated that the fluid passageways 49 may have open areas which are larger or smaller than the cross sectional area of the inner dimensions of the bellows 40. The cap 45 is fastened to the upper end of the bellows 40 in a firm and fluid tight manner by any number of means which accomplish such a connection, and further, it is not necessary that the cap 45 be provided as a separate part, as it may be made integral to the bellows 40.

[0044] Referring to FIG. 4, a perspective view of the rigid tube which encloses and restrains the bellows 40 of a first embodiment of the present invention from lateral movement will be described. The bellows 40, an axis of which is vertical, is fitted within and enclosed by a rigid tube 50, an axis of which is also vertical, and through which a plurality of slots 51 along the length of its axis are provided. The rigid tube 50 is made of metal, plastic or any other material which has sufficient rigidity to maintain it at an axis which is vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces. The rigid tube 50 has an inner dimension which is sufficient to accommodate the outer dimension of the bellows 40, such that the bellows 40 is restrained against lateral movement, yet is free to expand upwardly when the fluid pressure in the interior of the bellows rises and thereby exerts a force on the underside of the cap 45 and raises the level of the fluid passageway 46 through the cap 45, to the prescribed level which produces the desirable release rate for the application. Although a plurality of slots 51 along the axis of the rigid tube 50 are depicted, only a single slot 51 is required, so long as its width is sufficient to pass the desirable release rate, while accommodating free discharge through the fluid passageway 46 provided through the cap 45.

[0045] Referring to FIG. 4A, a perspective view of an alternate rigid tube 50 which encloses and restrains the bellows 40 of a first embodiment of the present invention from lateral movement will be described. The bellows 40, an axis of which is vertical, is fitted within and enclosed by a rigid tube 50, an axis of which is also vertical, through which a plurality of openings 52 are provided near its lower end. The rigid tube 50 is made of metal, plastic or any other material which has sufficient rigidity to maintain it at an axis which is vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces. The rigid tube 50 has an inner dimension which is sufficient to accommodate the outer dimension of the bellows 40, such that the bellows 40 is restrained against lateral movement, yet is free to expand upwardly when the fluid pressure in the interior of the bellows rises and thereby exerts a force on the underside of the cap 45 and raises the level of the fluid passageway 46 through the cap 45, to the prescribed level which produces the desirable release rate for the application. Although a plurality of round openings 52 are depicted near the lower end of the rigid tube 50, only a single opening 52 of any geometric configuration is required, so long as the opening 52 has an area which is sufficient to pass the desirable release rate for the application, while accommodating a free discharge through the fluid passageway 46 provided through the cap 45.

[0046] Referring to FIG. 4B, a perspective view of an alternate means to restrain the bellows 40 of a first embodiment of the present invention from lateral movement will be described. The bellows 40, an axis of which is vertical, is fitted within and enclosed by an array of rigid bars 55, the axes of which are also vertical. The rigid bars 55 are made of metal, plastic or any other material which has sufficient rigidity to maintain them at an axis which is vertical and resist the forces of hydrostatic pressure which are anticipated to act on them. The array of rigid bars 55 has an inner dimension which is sufficient to accommodate the outer dimension of the bellows 40, such that the bellows 40 is restrained against lateral movement, yet is free to expand upwardly when the fluid pressure in the interior of the bellows rises and thereby exerts a force on the underside of the cap 45 and raises the level of the fluid passageway 46 through the cap 45, to the prescribed level which produces the desirable release rate for the application. The spaces 56 between the rigid bars 55 are sufficient to pass the desirable release rate for the application, while accommodating free discharge through the fluid passageway 46 provided through the cap 45. Although three rigid bars 55 are depicted, any number of rigid bars 55 may be provided so long as they arrayed in such a fashion as to restrain the bellows 40 from lateral movement and the spaces 56 between the rigid bars 55 are sufficient to accommodate free discharge through the fluid passageway 46 provided through the cap 45. Further, although the rigid bars 55 are depicted as having a round cross section, it is anticipated that they may be provided in any number of geometric cross sections such as rectangular or tubular.

[0047] Referring to FIG. 4C, a perspective view of the rigid tube 50 which encloses and restrains the bellows 40 of a third embodiment of the present invention from lateral movement will be described. The bellows 40, an axis of which is vertical, is enclosed within a rigid tube 50, an axis of which is also vertical, and has two slots 51 along the length of its axis. The slots 51 are of sufficient width to freely accommodate the outer dimension of the tubular shaped, fluid passageways 49 protruding from the cap 45, which has been fitted to or made integral to the distal, upper end of the bellows 40. The rigid tube 50 is made of metal, plastic or any other material which has sufficient rigidity to maintain it at an axis which is vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces. The rigid tube 50 has an inner dimension which is sufficient to accommodate the outer dimension of the bellows 40, such that the bellows 40 is restrained against lateral movement, yet is free to expand upwardly when the fluid pressure in the interior of the bellows rises and thereby exerts a force on the underside of the cap 45 and raises the level of the tubular shaped fluid passageways 49 provided through the cap 45, to the prescribed level which produces the desirable release rate for the application. Although two slots 51 and two, tubular shaped fluid passageways 49 which protrude from the cap 45 and through the slots 51 are depicted, any number of slots 51 and tubular shaped, fluid passageways 49 may be provided, so long as the total area of the tubular shaped fluid passageway 49 or fluid passageways 49, as the case may be, have an area which is sufficient to limit discharge to the desired release rate.

[0048] Referring to FIG. 5, a schematic view of an alternate system of the present invention will be described. The flow control system 30 is incorporated into a holding tank 4 wherein the fluid 3, stored in the holding tank, is flowing through the flow control system 30 and into a downstream drainage system 60. The flow control system 30 is positioned beneath an optional accessway 5, through the top of the holding tank 4, such that the flow control system 30 is easily accessed from the surface for inspection or maintenance. The accessway 5 is depicted as a manhole rim and cover; however, in some embodiments, it is anticipated that the accessway 5 may be provided in the form of a catch basin grate, hatch cover or any number of other suitable means to provide access from the surface into the interior of the holding tank 4. The closed conduit 31 is made of plastic, metal, concrete or any other material which is suitable for conveying the fluid 3, and is connected to the upstream reservoir 1 below the fluid surface 2. The downstream end of the closed conduit 31 is oriented such that its exit is directed upward and it is interfaced to the lower end of an expanding conduit provided in the form of a bellows 40. The upstream end of the closed conduit 31 is equipped with an optional baffle 32, to prevent entry of undesirable materials such as trash, debris, greases, oils and the like from entering or possibly interfering with the operation of the flow control system 30. Although the optional baffle 32 is depicted in the form of an elbow oriented such that its entrance is directed downward, there are many ways to protect the inlet of the closed conduit 31 from the unwanted entry of undesirable materials. In some embodiments it is anticipated the closed conduit 31 may be protected by a screen, or by connecting its inlet to a surface skimming device.

[0049] The bellows 40 has an axis which is vertical and is made from rubber, polyurethane, plastic or any other any reasonably flexible, resilient and impervious material suitable for conveying the fluid 3. Although there are many ways to interface the lower end of the bellows 40 to the closed conduit 31, the lower end of the bellows 40 is connected to the closed conduit 31 by means of a flanged connection 35. In some embodiments it is anticipated the lower end of the bellows 40 has collar which fits tightly over the outside of the closed conduit 31 and is fastened to the closed conduit with clamps.

[0050] The distal, upper end of the bellows 40 is equipped with a cap 45 which is made from metal, plastic or any other sufficiently rigid material suitable for exposure to the fluid 3. The cap 45 has at least one fluid passageway 46 which provides an opening from the interior of the bellows 40. The fluid passageway 46 is oriented vertically or horizontally and has an open area which is smaller than the cross sectional area of the inner dimension of the bellows 40. In some embodiments, the cap 45 is a component which is separate, and is fastened to the upper end of the bellows 40. In other embodiments, the cap 45 is made integral to the bellows 40.

[0051] The bellows 40 is enclosed by a rigid tube 50, an axis of which is vertical, and which has a slot 51,provided along the length of its axis, of sufficient width, such that the interior of the rigid tube 50 is freely and fluidly connected to the interior of the container 20. Although only a single slot 51 is shown, it is anticipated that in some embodiments there may be more than one slot 51. The interior dimension of the rigid tube 50 is sufficient to accommodate the exterior dimension of the bellows 40 such that the bellows 40 is free to expand upwardly, yet is restrained from moving laterally. The rigid tube 50 is made of metal, plastic or any other material which is sufficiently rigid to maintain its axis vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces.

[0052] The container 20 can be fashioned from materials such as concrete, metal, plastic or any other material or combination of materials which provide adequate structural integrity and are also reasonably impervious and suitable for exposure to the fluid 3. The upper end of the container 20 is open and its upper rim 91 is positioned at a prescribed level such that if the fluid surface 2 rises above the level of the upper rim 91 of the container and the volumetric capacity of the holding tank 4 is at risk of being exceeded, the container 20 can also function as an overflow riser and provide a means to accommodate an increased rate of discharge. In some embodiments, the upper rim 91 of the container 20 may be notched, in any number of geometric configurations, to create one or more additional overflow weirs at prescribed levels below the upper rim 91 of the container 20. Although it is most convenient to utilize the container 20 as the means to provide an increased rate of discharge when the volumetric capacity of the holding tank 4 is at risk of being exceeded, it is not required. In some embodiments it is anticipated that a separate means to provide overflow control will be provided. The container 20 has also been fitted with additional, optional, inlets 92, which open from the interior of the holding tank 4 into the interior of the container 20, at prescribed levels, and provide a means to gradually increase the rate of discharge through the flow control system 30 as the fluid surface 2 in the holding tank 4 rises. Although two inlets 92 are depicted, it is anticipated there may be any number of inlets 92 positioned at varying and prescribed levels along the vertical axis of the container 20. Although the flow control system 30 is depicted as being positioned within the holding tank 4, it is not required. In some embodiments it is anticipated that the container 20 may be located outside of the holding tank 4 and is housed in a separate chamber, such as a manhole, which is fluidly connected to the interior of the holding tank 4 and downstream drainage system 60.

[0053] Referring to FIG. 6, a schematic view of a second alternate system of the present invention will be described. The flow control system 30 is incorporated into the bank of a reservoir 1 and is fluidly interfaced to the reservoir 1. The flow control system 30 is positioned beneath an optional accessway 5, through the top of the container 20, such that the flow control system is easily accessed from the bank of the reservoir 1 for inspection or maintenance. The accessway 5 is depicted as a catch basin grate; however, in some embodiments, it is anticipated that the accessway 5 may be provided in the form of a manhole rim and cover, hatch cover or any number of other suitable means to provide access from into the interior of the container 20 from above. The closed conduit 31 is made of plastic, metal, concrete or any other material which is suitable for conveying the fluid 3, and is connected to the upstream reservoir 1 below the fluid surface 2. The downstream end of the closed conduit 31 is oriented such that its exit is directed upward and it is interfaced to the lower end of an expanding conduit provided in the form a bellows 40. The upstream end of the closed conduit 31 is equipped with an optional baffle 32, to prevent entry of undesirable materials such as trash, debris, greases, oils and the like from entering or possibly interfering with the operation of the flow control system 30. Although the optional baffle 32 is depicted in the form of an elbow oriented such that its entrance is directed downward, there are many ways to protect the inlet of the closed conduit 31 from the unwanted entry of undesirable materials. In some embodiments it is anticipated the closed conduit 31 may be protected by a screen, or by connecting its inlet to a surface skimming device.

[0054] The bellows 40, has an axis which is vertical, and is made from rubber, polyurethane, plastic or any other any reasonably flexible, resilient and impervious material suitable for conveying the fluid 3. Although there are many ways to interface the lower end of the bellows 40 to the closed conduit 31, the lower end of the bellows 40 is connected to the closed conduit 31 by means of a flanged connection 35. In some embodiments it is anticipated the lower end of the bellows 40 has a collar which fits tightly over the outside of the closed conduit 31 and is fastened to the closed conduit with clamps.

[0055] The distal, upper end of the bellows 40 is equipped with a cap 45 which is made from metal, plastic or any other sufficiently rigid material suitable for exposure to the fluid 3. The cap 45 has at least one fluid passageway 46 which provides an opening from the interior of the bellows 40. The fluid passageway 46 is oriented vertically or horizontally and has an open area which is smaller than the cross sectional area of the inner dimension of the bellows 40. In some embodiments, the cap 45 is a component which is separate, and is fastened to the upper end of the bellows 40. In other embodiments, the cap 45 is made integral to the bellows 40.

[0056] The bellows 40 is enclosed by a rigid tube 50, an axis of which is vertical, and which has a slot 51 provided along the length of its axis, of sufficient width, such that the interior of the rigid tube 50 is freely and fluidly connected to the interior of the container 20. Although only a single slot 51 is shown, it is anticipated that in some embodiments there may be more than one slot 51. The interior dimension of the rigid tube 50 is sufficient to accommodate the exterior dimension of the bellows 40 such that the bellows 40 is free to expand upwardly, yet is restrained from moving laterally. The rigid tube 50 is made of metal, plastic or any other material which is sufficiently rigid to maintain its axis vertical and resist the forces of hydrostatic pressure which are anticipated to act on its interior surfaces.

[0057] The container 20 can be fashioned from materials such as concrete, metal, plastic or any other material or combination of materials which provide adequate structural integrity and are also reasonably impervious and suitable for exposure to the fluid 3. An overflow weir 93 is provided, at a prescribed level, through the wall of the container 20 that is in communication with the fluid 3 in the reservoir 1. The overflow weir 93 provides a means to accommodate an increased rate of discharge when the volumetric capacity of the reservoir 1 is at risk of being exceeded. The overflow weir 93 may be provided in any number of geometric configurations and any number of prescribed levels. Further, it is also anticipated there may be more than one overflow weir 93 provided through the walls of the container 20 which are in communication with the fluid 3 in the reservoir 1. Although it is most convenient to utilize the container 20 as the means to provide an increased rate of discharge when the volumetric capacity of the reservoir 1 is at risk of being exceeded, it is not required. In some embodiments it is anticipated that a separate means to provide overflow control will be provided.

[0058] The bellows 40 is depicted in a less than fully expanded state and the fluid passageway 46 through the cap 45 is at an initial level, at which the fluid surface 2 in the reservoir 1 is at the same level, and is the minimum, controlled level, at which there is no flow and no discharge of fluid 3 from the flow control system 30 into the downstream drainage system 60; however, the container 20 has also been fitted with additional, optional, inlet 92, which opens from the reservoir 1 to the interior of the container 20. The optional inlet 92 is depicted below the fluid surface 2 in the reservoir 1, and fluid 3 is flowing through the optional inlet 92 into the interior of the container 20 and out into the downstream drainage system 60. When the optional inlet 92 operates at levels below the initial, minimum, controlled level, it provides a means to drain the level of the reservoir 1 below the initial, minimum, controlled level. Although, only one optional inlet 92 is depicted, it is anticipated there may be a plurality of optional inlets 92 depending upon the requirements of the specific application. Further, it is anticipated that any number of optional inlets 92 may be provided above the initial, minimum, controlled level depending on the requirements of the specific application to provide a means to gradually increase the rate of discharge through the flow control system 30 as the fluid surface 2 in the reservoir 1 rises.

[0059] Although the flow control system 30 is depicted as being positioned in the bank of the reservoir 1, it is not required. In some embodiments it is anticipated that the container 20 may be located some distance downstream from the reservoir 1 and is housed in a separate chamber, such as a manhole, which is fluidly connected to the reservoir 1 and the downstream drainage system 60.

[0060] Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result.

[0061] It is believed that the system and method of the present invention and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.