Adjustable resistance, gravitationally activated, anti-siphon valve

1. An anti-siphon drainage device, comprising:

a housing forming an internal chamber;

an inlet port and an outlet port communicating with the internal chamber and fluidly connected by a primary flow path;

a valve seat associated with the primary flow path;

a sloped section extending from the valve seat inside the internal chamber;

a valve element disposed in the sloped section and capable of seating in the valve seat to restrict a fluid flow into the primary flow path from the inlet port;

a secondary flow path comprising an opening disposed approximate to the inlet port and an orifice disposed approximate to the outlet port; and

a regulator comprising an aperture to selectively open and close the opening of the secondary flow path,

wherein when the valve element is disposed in the valve seat and restricting the fluid flow into the primary flow path, the fluid flows into the secondary flow path.

2. The anti-siphon drainage device of claim 1 , wherein when the inlet port is disposed approximately above the outlet port in a vertical direction, the valve element is disposed in the valve seat and restricting the fluid flow to the primary flow path, and

wherein when the inlet port is disposed approximately parallel the outlet port in a horizontal direction, the valve seat allows the fluid flow into the primary flow path.

3. The anti-siphon drainage device of claim 1 , wherein at least one of the valve element and the valve seat allow a restricted fluid flow into the primary flow path when seated.

4. The anti-siphon drainage device of claim 1 , wherein the primary flow path is hydraulically larger than the secondary flow path.

5. The anti-siphon drainage device of claim 1 , wherein the secondary flow path is spiraled around the primary flow path.

6. The anti-siphon drainage device of claim 5 , further comprising a second secondary flow path separate from the secondary flow path and comprising a second opening,

wherein the secondary flow path and the second secondary flow path are spiraled around the primary flow path as a double threaded screw, and

wherein the regulator further comprises a plurality of second apertures, which along with the aperture, are configured to selectively open and close the opening and the second opening.

7. The anti-siphon drainage device of claim 1 , further comprising:

a second secondary flow path separate from the secondary flow path and comprising a second opening; and

a third secondary flow path separate from both the secondary flow path and the second secondary flow path, and comprising a third opening,

wherein the regulator further comprises a plurality of second apertures, which along with the aperture, are configured to selectively open and close the opening, the second opening, and the third opening.

8. The anti-siphon drainage device of claim 7 , wherein the regulator can selectively open and close the opening, the second opening, and the third opening in at least one of the following configurations: all open, all closed, each of the openings individually opened, and pairs of openings opened.

9. The anti-siphon drainage device of claim 8 , wherein the primary flow path has a primary hydraulic capacity (P 1 ), the secondary flow path has a secondary hydraulic capacity (F 1 ), the second secondary flow path has a third hydraulic capacity (F 2 ), and the third secondary flow path has a fourth hydraulic capacity (F 3 ), and

further comprising a hydraulic relationship comprising: F 1 <F 2 <F 3 <P 1 .

10. The anti-siphon drainage device of claim 9 , wherein the hydraulic relationship comprises: F 1 <F 2 <F 1 +F 2 <F 3 <F 1 +F 3 <F 2 +F 3 <F 1 +F 2 +F 3 <P 1 .

11. The anti-siphon drainage device of claim 1 , wherein the disposition of the valve element in the valve seat is controlled by gravity.

12. A method of forming an anti-siphon drainage device, having a housing forming an internal chamber; an inlet port and an outlet port communicating with the internal chamber and fluidly connected by a primary flow path; a valve seat associated with the primary flow path; a sloped section extending from the valve seat inside the internal chamber; a valve element disposed in the sloped section and capable of seating in the valve seat to restrict a fluid flow into the primary flow path from the inlet port; a secondary flow path; and a regulator, wherein when the valve element is disposed in the valve seat and restricting the fluid flow into the primary flow path, the fluid flows into the secondary flow path, comprising the steps of:

forming the primary flow path with the valve seat;

disposing the valve element in the sloped section;

forming the secondary flow path; and

disposing the regulator over the secondary flow path to selectively occlude the secondary flow path.

13. The method of claim 12 , wherein the method of forming the secondary flow path comprises spiraling the secondary flow path around the primary flow path.

14. The method of claim 12 , further comprising the steps of:

forming the primary flow path with a first hydraulic characteristic; and

forming the secondary flow path with a second hydraulic characteristic,

wherein the first hydraulic characteristic is greater than the second hydraulic characteristic.