Valve construction and method of making the same

摘要

A valve construction and method of making the same are provided, the valve construction having an annular valve seat and a movable valve member for opening and closing the valve seat and being operatively interconnected to a thermal power element that is carried by the valve construction. The valve member has an annular rigid part for engaging the valve seat and has an annular flexible part for also engaging the valve seat at a point upstream of the rigid part, the parts of the valve member being so constructed and arranged that the rigid part moves out of engagement with and away from the valve seat a certain distance before the flexible part moves out of engagement with the valve seat. The flexible part of the valve member has an opening therethrough that is adapted to provide a certain sized fluid flow path through the flexible part of the valve member when the rigid part of the valve member is engaging the valve seat.