Check valve with means for relieving fluid pressure from the control chamber

Claim 1

A check valve for use in a vacuum operated power braking system to relieve fluid condensation created by petroleum fumes from the manifold of a vehicle comprising: a housing having a control chamber with an inlet port connected to the braking system, a first outlet port connected to the manifold where a partial vacuum can be created and a second outlet port connected to the atmosphere; flexible means located in the control chamber overlying said inlet port and adapted to be seated on the housing surrounding said inlet port when said partial vacuum has evacuated said braking system of air, said flexible means upon seating on said housing preventing said petroleum fumes from entering said braking system; a tubular projection surrounding said second outlet port; cylindrical means having a spherical head loosely located in the interior of said tubular projection; and pin means for retaining said cylindrical means in said tubular projection, said cylindrical means engaging the interior of said tubular projection to align said spherical head with said second outlet port, said cylindrical means moving in response to said partial vacuum to seat said spherical head on the housing surrounding said second outlet port and allow said partial vacuum to evacuate air from said inlet port through said first outlet port, said petroleum fumes and condensation resulting therefrom passing between the interior of the tubular projection and the cylindrical means to harmlessly escape through the second outlet port without damaging said flexible means when partial vacuum is absent at the manifold.