Roof draining systems

Claim 1

In combination with a substantially horizontal roof, a roof draining system for draining away water that accumulates on the roof, said roof draining system comprising, a. at least two sumps installed on said roof, including one of which is a control sump, b. at least two siphon pipes, each pipe having an intake end and a discharge end, the intake end of one of said pipes extending into said control sump substantially to the bottom thereof and the intake end of each of the other siphon pipes extending into one each of the other said sumps substantially to the bottoms thereof, each of said siphon pipes extendIng therefrom over the edge of said roof and downwardly to their respective discharge ends, c. a priming-discharge pipe for initiating the siphoning action of said siphon pipes, said priming-discharge pipe having an inlet end and a discharge end, said priming-discharge pipe extending from said inlet end across said roof and over the edge of said roof downwardly to its discharge end, the discharge end of the siphon pipe associated with said control sump being connected to the downwardly extending portion of said priming-discharge pipe between said roof edge and the discharge end of said priming-discharge pipe, and the discharge end of each of said other siphon pipes being connected to the downwardly extending portion of said priming-discharge pipe at vertically spaced intervals between the connecting point of said first connected siphon pipe and the discharge end of said priming-discharge pipe, d. means for introducing water into the inlet end of said priming-discharge pipe connected to said means, e. a water detecting probe extending into the control sump in spaced relation with the bottom of said control sump, and f. control means operatively connected to said probe, said control means connected to and actuating said means for introducing water to said priming-discharge pipe when said probe detects water in said control sump.