Background of the Invention U. S. Patent No. 5,244,309 discloses a fluid flow control device wherein various layers of reinforcement such as fabric are imbedded in a slab of rubber of substantial thickness. The device is then secured to the top of a dam in a vertical direction to control the volume of water behind the dam.

To produce the device of the 309 patent requires that the complex arrangement of the reinforcement fabric be built in for each individuai application and would not be adjustable.

Summary of the Invention In accordance with the practice of the present invention, there is provided a rubber gate comprised of a plurality vertical layers of conveyor belting of different heights stack horizontally in adjacent relationship and secured to the top of a dam to restrain the overflow of water. In another embodiment, the layers of conveyor belting can be of the same height but of varying thickness. A third embodiment is comprised of layers of conveyor belting with varying heights and varying thickness.

Brief Description of the Drawing Figure 1 is a cross-sectional of a rubber gate according to the invention.

Figure 2 is a cross-sectional view of another embodiment of a rubber gate according to the invention.

Figure 3 is a cross-sectional view of another embodiment of a rubber gate according to the invention.

Detail Description of the Invention The rubber gate shown generally at 10 is comprised of a plurality of layers 12,14 and 16 of conveyor belting extending vertically from a dam 18 and stacked horizontally to restrain the volume of water 20 by virtue of the stiffness of the rubber and/or reinforcement 22. Various combinations are contemplated such as in Figure 1 wherein the belting layer 12a, 12b, 12c and 12d are of equal thickness and varying height. In Figure 2, the belting layers 14a, 14b, 14c and 14d are of varying thickness

and varying height. In Figure 3, the belting 16a, 16b, 16c and 16d are of equal height and varying thickness.

The belting can be reinforced as shown at 22 in Figures 1 and 3 or not reinforced as shown in Figure 2. In this new design, the arrangement of the number and thickness of the belt layers controls the stiffness, allowing the design to be field- adjusted at each site where the rubber gate is fastened to the dam 18 by means such as angle irons 24 fastened by bolts 30.

The belting layers 12,14 and 16 can be fastened to the angle irons 24 by bolt 26 and nut 28.

The operation of the rubber gate 10 is illustrated in Figure 3 wherein when the level of the water 20 rises sufficiently to overcome the stiffness of the layers of conveyor belting 16, the layers of belting bend over as shown by the phantom lines to release the water until the stiffness of the belting overcomes the water pressure and returns to its upright condition.

While certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in this art that various changes and modifications may be made therein without departing from the spirit or scope of the invention.