Patent ID: 8001989

Claim:
A flow control device comprising: an annular housing having a peripheral wall and side walls which provide an enclosure for a body of liquid swellable material, the peripheral wall of the housing having one or more orifices providing inlet ports for liquid flow into the housing one of said side walls of the housing to be located in a downstream position of the device having an outlet opening for liquid flow out of the housing and the other side to be located in an upstream position being closed; and a body of a liquid swellable material located in the housing having an upstream side, an outer periphery and a downstream side in relation to the direction of liquid flow through the device, the body of liquid swellable material within the housing having an encircling sealing layer around its outer periphery to engage the inner periphery of the housing when the body of material is in a swollen condition from contact with liquid to close off flow of liquid through the housing and to allow liquid flow through the housing when the body of swellable material is in its contracted condition.