Patent ID: 8272398

Claim:
A valve assembly for a tank comprising: a housing having a housing portion located at least partially outside of the tank, wherein the housing defines a vapor passage; a carrier secured to the housing, wherein the carrier defines a carrier opening; a membrane attached to the carrier such that the carrier opening is between the membrane and the vapor passage and the membrane covers the vapor passage and the carrier opening to allow the passage of vapor through the membrane to the carrier opening and the vapor passage and prevent the passage of liquid through the membrane; a flow control feature supported by the carrier such that the flow control feature is between the carrier opening and the vapor passage; wherein the flow control feature is configured to provide a variable flow rate of vapor that has passed through the membrane; wherein the flow control feature is a head valve; wherein the head valve further comprises a disc located in the vapor passage of the housing on a vapor recovery side of the carrier; and wherein the disc further defines a disc opening configured to provide continuous fluid communication between the carrier opening and the vapor passage.